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Making A 1,500-Plus Horsepower Honda B18 Engine Live


This is the story of opportune meetings, overcoming odds, and unrelenting levels of girl power. It is also the story of an undersized Honda Civic, its equally tiny engine, and the tenacity that it takes to become one of the fastest front-wheel-drive drag racers on the planet.

For Process Development Manager, Nichole Elff, adrenaline has been a core component in her life for as long as memory serves. So when she was introduced to the import scene back in college, her interests pivoted from horseback riding, to customizing cars with friends on the weekends. The following twenty-year import automobile love affair would see Nichole start with a 1994 Acura Integra rocking basic bolt-ons, to what what you see here today: A dedicated XFWD championship Honda race car driver with stacks of wins to her name, including the title of 2nd fastest FWD female driver in history.

All of this has been made possible by a surprisingly small powerplant: A 119ci 4-cylinder B18 Honda engine that puts down around 1,500 wheel-horsepower. If our math is correct, that averages out to an astonishing 12.6 horsepower per cubic inch. Compare that to a Pro Modified car, which is averaging anywhere from 7 to 8 hp/ci, and you can see the performance appeal of this Honda platform. However, what you don’t see are the tuning and engine-building challenges of running a dedicated race program that can safely and consistently supply these extremes, which as Nichole explains translates to, “…overbuild, demand high quality, and constantly seek out the weakest link.”

These values have also helped determine how Nichole’s Civic engine gets rebuilt after every other event or so. For as she is quick to admit, there is always room for improvement on her overbored B18C Honda motor, with the latest and greatest being of particular interest to us here at EngineLabs.

Miss PSI 1500whp 119ci Honda B18 Motor

Elff’s best time in her 1992 Honda Civic is a 7.78 at 196mph, which at the time of this writing, makes her the seventh-quickest XFWD competitor in the world, and the second-fastest FWD female driver of all time.

Indy Racing and High-Speed Honda Goals

As for the racing side of this story, that all starts way back in 2006 when Nichole moved to Indianapolis. It was there that she became part of a car forum called IndyHP, where she met her eventual husband, Damon.  A 2007 trip to a NOPI Drag Racing Association event marked Nichole’s first time seeing ProFWD and SFWD racing, and it blew her mind that these cars were running nines in the quarter-mile. An event that left such a memorable impression, that she returned home, fully determined to start her own SFWD Honda Civic build.

Flip forward a decade, and Nichole was still sitting in the grandstands. The year was 2018, and while she had been actively competing for years, her Honda was just a tenth off of the minimum ET requirement to be labeled as a True Street WCF competitor. The following year, she officially qualified for WCF, where she made it all the way to the quarter-finals that year. She told herself that if she broke cage certification (8.50) it was time to jump head-first into drag racing. She proceeded to run an 8.49 in the first round of eliminations and that pretty much changed everything.

King offers rod bearings for aluminum rods with locating dowels. These extreme-duty components are required for such insane cylinder pressures.

The following year, in 2020, Nichole bought a fresh Honda Civic chassis, which quickly transformed into the “Miss PSI” car you see today. Come 2021, Nichole’s husband left professional racing so that he could focus full-time on his wife’s drag racing passion while growing his tuning presence via his business, Demon Motorsports. This decision proved fruitful, and that year brought with it runner-up finishes at the car’s first two events, before finishing off the season with the couple securing a WCF True Street win.

By 2022, Nichole and Damon had swapped in a much larger Precision Next Gen R 73.9 turbo to help break into the elusive seven-second zone. An accomplishment that would eventually be obtained during a 2022 FL2K qualifying round, making Nichole the first female in XFWD history to run a seven-second pass. Later in that same event her Honda ran a 7.84 and put its driver on the world’s top 10 list. 2023 brought with it a 7.78 at 196mph pass, thus making Miss PSI the 7th fastest competitor in the world and the 2nd fastest FWD female of all time. 

The XFWD class is full of gear-banging adrenaline junkies that are constantly balancing the knife edge of performance, traction, and guts.

The XFWD class is full of gear-banging adrenaline junkies that are constantly balancing the knife edge of performance, traction, and guts.

XFWD FTW PPL!

Being that this is an “XFWD” (Xtreme Front Wheel Drive) Challenge program we speak of, one of the biggest challenges is keeping the engine alive long enough to go the distance and compete in all rounds. Having enough performance left in the tank to compete in the final rounds, and occasionally turn things up a notch remains a concern at every race event.

One of the ways Nichole and Damon have been able to prolong the longevity of their Civic’s screamer of an engine is to check bearing wear after events, and then tear the engine down for a full inspection every two to three events. This may seem overkill (not to mention extremely time-consuming) but it allows Nichole’s team to address any underlying issues early on, and ascertain where weaknesses may be festering.

For instance, in 2022, the Miss PSI team’s biggest stumbling block was getting a head gasket to survive multiple events. They found out this was due to the amount of traction control needed for short-track grip. By moving the entire engine program over to a billet B-Series block from Bullet Race Engineering, the team was able to improve block rigidity and head gasket performance. This was achieved by the block’s larger, 14mm head studs and the company’s signature beryllium copper “Fire Ring” gasket set.

Being one of the few XFWD cars running a wet-deck billet block, the Miss PSI team had to work around (and through) quite a few learning curves to get optimal performance out of this fresh setup. But after a few missteps, the team came out swinging at the World Series of ProMod and ran a top event ET with a 7.78 at 196mph. This was when the car secured that aforementioned “7th fastest XFWD in the world” title.

We don’t normally dyno the engine to max power, but estimate 1,600 wheel-horsepower,  based on fuel consumption and trap speed. — Nichole Elff

Miss PSI 1500whp 119ci Honda B18 Motor

pMax Kote bearings from King Engine Bearings being installed into the Miss PSI Bullet Engineering billet B18 block, along with a set of BME aluminum rods.

Throughout the rest of the 2022 season, Nichole and her team continued to try fresh upgrades, with different rotating assembly combinations being the primary focus. Then, come mid-2023, the switch to pMax Kote main rod bearings from King Engine Bearings was made, which proved to be a very wise decision.

Remember a few paragraphs back, when we mentioned that checking the engine’s bearings after each event was a mandatory quality control procedure for this race team? Well just after the first event, the Miss PSI crew saw improved outcomes with that fresh King Bearings combo, with wear being minimized significantly. And so the team opted to run those same main bearings for all five of the final events, which in turn helped them win the 2023 FL2K XFWD Street class trophy, and a nice little chunk of change in prize money. 

After each event, a full engine teardown takes place back at the shop. Here, you can see that the bearings previously used in the Miss PSI B18 (TOP) came out worn to hell and back after a single event. Meanwhile, very little coating seems to have been removed from the units from King Engine Bearings.

The Importance of Being “Over-bearing”

Being that Damon is the mad scientist behind the keys to this machine, Nichole explains that his “forever job” is finding the optimal tune for the track that can bring that knife-edge balance of performance that his bride requires. Just another husband and wife team building a 1,500-plus horsepower Honda Civic in-house for fun.

And while Nichole counts herself extremely fortunate to have a partner who supports her “crazy passion,” she knows that he too enjoys taking his knowledge from Indycar and Sportscar racing and applying these innovative solutions to the Miss PSI race program. Together with the help of their small, but dedicated village, this car has skyrocketed to the top in record time.

 

According to Damon, switching the little Honda over to the pMax Kote series from King Engine Bearings in the middle of the 2023 season has been one of the most surprising game-changers for the team. Up until that point, it was common for the rod bearings to wipe the coatings right off after just a single event, whereas these pMax Kote units looked brand new race after race.

Not only does this specialized coating withstand the harsh environment found within this force-fed race engine, but the shape of the bearing itself refuses to warp like other products. This has resulted in greater reliability and performance as well.

The confidence that products such as these provide has allowed the team to push the platform harder than ever before, and set their sites on even greater heights in the 2024 race season. Nichole and Damon Elff aren’t done yet. Apparently, they now have their sights set on making Nichole the first XFWD driver in history to pilot a car to 200mph. No small feat for a little 1.9-liter four-cylinder engine. 

 

MissPSI XFWD Engine Spec Sheet

Owner: Nichole Elff
Age: 40
Occupation: Process Development Manager
Engine (Model or Family): Honda B18C
Builder: 4 Piston Cylinder Heads
Machine Shop (If different from builder): N/A
Total Displacement: 1.9 liters
Bore x Stroke: 84mm x 89mm
Block: Bullet Engineering Billet B-series
Crankshaft: OEM B18B
Bearings: King Racing PMaxKote
Rods: BME Aluminum
Pistons: CP
Rings (size, type, brand): Proprietary
Oil Pump: 4 Piston ported OEM pump
Oil Pan: Moroso
Timing Set: Gates timing belt & Ramey Racing adjustable cam gears
Cylinder Heads: 4Piston Outlaw Front Runner CNC Cylinder Head, 6mm Stub nose guides, A3
Beryllium valve seats
Port Work: 4 Piston
Valves: Ferrea super alloy plus valves, 4P 6mm exhaust valves,
Valve Springs: Ferrea valve springs, retainers, and locks
Flow numbers: will need to ask 4 Piston
Camshaft(s): Web Cams Turbo B-series roller camshaft
Rockers: Ferrea roller rocker
EFI System: Motec M150
Injectors: Injector Dynamics
Throttle Body: Proprietary
Intake Manifold: Skunk 2 Ultra Race Manifold
Headers: Speedfactory Forward Facing Manifold
Power Adder: Precision Next Gen R 73.9 turbo
Ignition System: Motec Ignition 1A coils
Fuel System: Weldon Mechanical fuel pump
Fuel Type: Methanol
Horsepower: 1,500 whp

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Turbo Failure And How The Correct Oil And Good Maintenance Can Help

It is no secret that dirty oil can really do serious damage to your engine. Left unchanged, used oil can allow bearings to prematurely wear, and other moving parts to come apart in grand fashion. Dirty oil can also be one of the biggest causes of turbo failure. Knowing this, I thought it might be time to take a look at how maintaining your engine oil quality is vital to keeping not only your engine healthy, but your turbo happy as well.

For starters, you need to understand how oil and lubrication are involved in optimizing turbo performance over the life of this device. Many studies have shown that contaminated oil is one of the biggest causes of turbo failures  in the diesel industry

Precise Spinning

Turbocharger bearings utilize incredibly precise operating tolerances and are subjected to unbelievably high rotational speeds. Together, this presents an engineering challenge that is vastly different from other bearing systems in an internal combustion engine.

turbo failure

To protect these mechanical marvels, the oil used to lubricate the bearings needs to be clean, the correct grade/viscosity, flow as needed, and be delivered immediately when the turbocharger starts to spin. If one or all of these does not occur, the turbo is sure to fail.

Viscous Support

Like engine bearings, turbo bearings rely on the hydrodynamic principle to survive. In other words, the oil supports the rotating parts, so they do not make physical contact as they spin. This support is highly reliant upon using the correct viscosity oil. With an improper viscosity, the oil will not reach the converging sections and no pressure will be generated.

A typical turbo can spin at upwards of 100,000 to 150,000 rpm, so the proper oil is needed to prevent the turbo-shaft bearings from failing. Oil is used to create a cushion between the moving parts of the turbo and to accomplish this, the turbo’s shaft must be perfectly balanced or no simple oil film will prevent it from tearing itself up at those high rotational speeds. In layman’s terms, the oil is too thin to properly support the shaft and it will contact the bearing with catastrophic results — turbo failure.

Not only is precision balance a must, but there must also be minimal play in the bearings. These two aspects work together to create zero lateral movement in the shaft. A high-quality oil is essential to protect the turbo in this harsh application of high temperature, high RPM, and very tight tolerances.

So, what is the best viscosity for a turbo? That is a question with many correct answers. What I mean is, the right viscosity will vary depending on where you live. For instance, Cummins recommends 15W-40 if living in a climate with temperatures greater than 10 degrees Fahrenheit. If your climate ranges between 0 to 30 degrees Fahrenheit and you do not use an engine heater, a 5W-40 is called for. However, if you live in the same 0- to 30-degree climate and use a block heater, 10W-30 is acceptable. In other words, trust your manufacturer’s recommendations — they have taken into account the needs of the turbo combined with the rest of the engine.

All those moving parts need the proper lubrication.

Keeping It Clean

Oil viscosity is one thing, but since oil is basically getting “dirty” as soon as an engine starts running, that means foreign substances such as dirt, debris, or (gasp) metal particles will quickly find their way into the oil that is used to cool and lubricate the turbocharger’s moving parts. This contamination will degrade the oil’s performance, increase wear, and cause permanent damage. When this occurs, expensive repairs or even complete replacement can be necessary.

There are a lot of potential ways that contaminants can become part of your lubricating lifeblood. What’s more, these contaminants can vary in size and properties, and each type possesses its own wear characteristics.

For example, combustion residue (carbon) can occur when incomplete or poor combustion takes place (think delete tune and blowing black smoke). Another cause could be heavy blowby because of cylinder and/or piston wear. Finally, leaking injector seals can allow excess fuel into the oil supply. This can ‘polish’ and degrade bearings and rotating parts.

Another contaminant to oil can be by way of engine component wear. As parts wear, minute metal particles can be suspended in the oil and will be delivered to the turbo via the turbo’s oil system. You can surely imagine how this can compromise bearing performance and longevity.

Keeping Turbo Failure At Bay

And if there is a more common way of having contaminated oil other than poor vehicle maintenance, I would like to know about it. Poor maintenance has been proven to lead to dirt and silica being found in engine oil. I don’t need to tell you what that can do to bearings, the turbo shaft, and the thrust assemblies. What I am stating, is to be sure and use a quality oil filter, and change it as recommended. But wait, there’s more…

If your engine’s Crankcase Ventilation System (CCV) is blocked-up because of poor maintenance, this can lead to a build-up of acid in the oil. No filtration system can fix this. When acid levels get out of whack, corrosion is your next concern. And you might not realize it, but your cooling system can also affect your oil quality.

turbo failure

Make sure the oil you are pouring into your engine is the right oil for your needs.

Let’s take for instance the cooling system in your truck has a leak. This could be because of a bad gasket or even a leaking EGR system. This can cause high levels of potassium in the oil. While the potassium itself might not cause a problem, the coolant surely can contaminate the oil and contribute to turbo failure.

It’s crucial to remember that it is not just that the turbo needs oil. It’s also critical to have the proper viscosity and clean oil as well. In case you are one of those readers that needs to know everything, the engineering definition of viscosity is the friction between oil molecules which generates a resistance to flow over a fixed surface. Hence the common reference to “thickness”.

What I am trying to tell you is that you need to have a proper maintenance schedule. If you are not keeping the oil as clean as possible and utilizing the proper viscosity oil, you are asking for trouble. Remember, both of those are a prerequisite to avoiding turbo failure and increasing turbocharger performance and longevity.

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Go With the Flow: Moroso Explains How Temps Tamper With Oil Movement

Everyone worries about oil pressure and engine temps, because that’s what most engine read-outs register. May those readings be bone stock or aftermarket in nature, these figures often get misinterpreted, even by seasoned weekend track warriors.

This is precisely why Moroso has recently decided to hone in on this key topic of discussion, giving its race engineering brainiacs the ability to go beyond the old “pressure vs. volume” argument, and discuss things like drain-back concerns, oil levels, pressure, and flow rates. All of which are important issues that must be taken into consideration when setting up an oiling system or diagnosing an issue. May it be one way or another, it all cycles back to oil temps, and here’s why…

Moroso Oil Pump tester

Scott Hall walks us through Moroso’s oil pump test rig.

Moroso Makes a Stand for Oiling Equilibrium

Recently, Scott Hall from Moroso shot the video embedded above and uploaded it to YouTube.

Apparently, a friend of Hall’s had a dry-sump system overflow on him upon engine warm-up at the race track, despite having been calibrated and filled with the requisite amount of oil.

According to Hall, the issue was caused by the system being set to run on a predetermined warm-up temp, and not at the higher heat levels one encounters after a few passes have been made. So once that sump setup got “track hot,” it turned into quite the hot mess. Literally…

To help illuminate what was going on behind the scenes, Hall took it upon himself to conduct a little testing over at the Moroso Assembly Department. There, Moroso’s oil pump test stand was put to use, all in the hopes of showing how both internal dry sumps and external wet sump systems operate and fluctuate under varying levels of heat.

Those of you who are familiar with Moroso’s history may recall that this is the same test stand that made sure Dick Moroso’s oiling units were working correctly back in the day. Later, it served as the diagnostics lab for the systems that lubricated and cooled various Xfinity team vehicles.

Nowadays, the test stand is part torture tester and digital read-out lab, and part historical monument of sorts. Outfitted with the latest RacePak data acquisition sensors, a laptop, and a team of highly trained specialists like Scott Hall, this test stand allows Moroso to inspect and illuminate all types of oiling topics. The significance of oil temps and how they affect flow being their most recent endeavor.

Moroso chose to use RacePak’s IQ3 display and datalogger to be able to accurately monitor all of the channels required by the test stand.

Under Pressure…

To demonstrate how flow rates change when oil temps rise (or fall), Moroso needed to take its test stand, and adjust the resistance (i.e. oil pressure) levels within the system itself. 

But before diving into all that noise, Moroso points out that its test stand “…doesn’t take into consideration the expansion of the engine and… there are far too many variables that exist…”

Instead, Moroso says that testing an oil pump against a set parameter, and not just focusing on how the engine is influencing or reacting to the oil pump is key. 

To adequately monitor what actually matters, Moroso utilized one of RacePak’s digital data acquisition systems. The IQ3 model then allowed Hall to monitor temps, oil pressure (both before and after the filter), as well as oil filter shakedown schematics in case further testing was required. A flow meter was also implemented to measure movement in gallons per minute, while crankcase vacuum monitoring was registered up top for good measure in case things pertaining to blow-by became an issue.

For dry-sump pump monitoring, Moroso utilized a box that simulates an oil pan, thus allowing the team to adjust vacuum levels as needed. This was done because no two custom engine builds (or oiling systems) are the same. Additionally, a 10-quart oil tank with heating and cooling functions was brought in to allow a far more real-world simulation to occur quickly and effectively.

Finally, things like horsepower draw were measured via the use of kilowatt read-outs, with a focus on high-performance track car power being the focal point of the test video.

Let’s Talk Temps for a Tick

In the video, Hall explains that the oil pump was driven at 1,250 rpm, while maintaining 60 psi across the board. This translated to the oil pump cycling around 4.1 gallons per minute, before the oil was heated-up.

Testing started with oil temps registering 80 degrees Fahrenheit. Oil temps were then tweaked in 20-degree increments to showcase what changes look like when the pressure remains constant, but temperature increases.

According to Hall’s calculations, if water temps register 160 to 170 degrees after a little pre-race warm-up action, that oil will have likely have only just begun to hit the 100-degree mark. This translates to approximately 1 gallon-per-minute increase in flow. So although engine temps may have spiked by 80 degrees, oil temps only jumped 20 degrees or so by that point.

The results show that at the same pressure, as the temperature increases, the viscosity decreases, and subsequently, flow increases.

Do a burn-out, followed by a hot lap, and chances are your oil is hitting 140 degrees, which translates to 5.7 gallons of flow per minute at 60 psi. Complete a few more passes without incident, and that flow rate will likely sit at 7.0 gallons per minute, with internal oil temps hovering in the 160-degree range. All told, this would likely translate to the pressure changing about 10 psi during that time, and the flow increasing exponentially.

The Hot Oil Rub

So what does that mean for us automotive enthusiasts? A whole lot of doubling-down really.

In essence, doubling your oil’s temperature translates to doubling its flow rate, so make sure you know precisely what temp your oil is sitting at when you check its flow rate and pressure. This can make a massive difference in how effectively that lubricant circulates within the engine itself, but also how well it cycles back into your engine’s oil pan and onboard pump system.

Who knows? Chances are you may not have an oiling issue after all, just inadequate readings, or readings pulled at the wrong time.


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Forged vs Billet: Callies Explains Crankshaft Choices

When we began our conversation with Brook Piper at Callies Performance Products, our conversation humorously compared crankshafts and baking cookies. When you consider the metallurgy and machining processes involved with a racing crank, there are many variables to create a good cookie… er, crankshaft.

The left is a Callies Performance Products billet steel crankshaft, while a Ford forged 4340 Magnum crank from Callies is on the right.

4340 Crankshafts

The Forged 4340 crank is created with a process that matches its title. The “4340” references the alloy of metals, while “forging” describes the heating and compressing of the metal into forging dies on a multi-ton press.

“What qualifies as 4340 steel is a broad term,” Piper describes. “Many parts of the world struggle with material cleanliness, but it still reaches the parameters as a 4340 material. Callies acquires different raw materials from all over the world to create what we think is the purest SAE 4340 billet that goes into our forged Magnum crankshaft line.”

High heat and tons of pressure stamp the 4340 metal in a mold into its general shape, while a billet crankshaft begins as a cylinder of high-strength alloy with massive amounts of material machined away.

The Compstar line of forged 4340 crankshafts is a more affordable option; these cranks are forged overseas in Callies-owned dies, rough machined to pre-finish dimensions, and completed in Ohio.

“One key difference between Callies in-house and overseas materials is that they can’t get as much nickel in the 4340 material as we can stateside. They also have energy restrictions there which limit heat treating and nitriding processes. We can achieve more surface hardness here,” Piper describes.

Everything that makes a crank’s alloy strong is there for a reason. Nickel makes it tough, silicone provides machinability, and carbon makes it better to harden. There’s a real recipe to it. – Brook Piper, Callies Performance Products

That said, the Compstar line still has cost-effective value as a racing crank to limit at approximately 1,000 horsepower. “We are approximating our horsepower claims because we want to talk to our customers,” Piper says. ‘Many variables like car weight, drivetrain, normally aspirated/nitrous/boosted parameters may alter our recommendations.”

Side-by-side cutaways between a billet and forged crankshaft illustrate the difference between the alloys’ grain structure. The forged crankshaft (left) shows how it achieves its strength by compressing the material, and the tighter grain flows along the length. The billet grain (right) flows straight, but the material is far stronger in this condition.

Piper continues, “Let’s say an enthusiast wants a big-block crank for 800 horsepower. Our Compstar will do that all day long. If they want American-made with a longer life, they will be spending 3,000 dollars for a billet crank, but that’s what we do. We sit down and try to cater to a customer’s needs.”

Billet Crankshafts

Production of a billet crank is very different from a 4340 forging — the process will quickly explain why there is a higher price point.

Callies’ precision CNC and lathe centers do all of the machining processed by their Ohio craftsmen on their Billet and Magnum line cranks, while the Compstar line arrives rough machined and finished in-house.

Compared to a forging shaped with presses and dies, the Callies Ultra and Magnum billet cranks are machined from a solid bar of high-strength steel alloy. That is a lot of machining and wear on equipment. In Callies’ case, the billet material is typically a 4330 material. This alloy may sound close to a 4340 number, but it is a highly different alloy with more premium steel.

“We also use an EN30 steel that offers additional strength for huge cubic inches, longer spread bore blocks and nitro applications,” Piper explains.

Callies, crankshaft, crankshafts, billet, forged

Another variable is life expectancy. The Callies team can’t stress enough that they want to help enthusiasts decide between a billet crank’s life and strength option, or possibly replace your 4340 crank in less time. It’s all in the alloy “recipe.” If you’re in the market for a new crankshaft, give them the team at Callies a call to discuss the best choice for your application.


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Identifying Unknown Pistons And Rods On The Fly

When it comes to this hobby, not everyone has a spare pile of cash for parts. That often leads to scouring the internet, swap meets, and junkyards for second-hand deals on usable parts, like pistons and rods. There’s no shame in deal-hunting; it’s an interesting hobby where enthusiasts have to be both good investigators and negotiators. There are deals to be found, but even the best of deals is a bad deal, if they are the wrong parts.

So, we’re not going to even try and give you negotiation lessons, as in the last few deals we’ve made, we paid full ask because we needed the parts and didn’t want to risk losing the deal over a little haggling — the antithesis of the deal-hunter’s ethos. But, what we can walk you through, is how to determine what you’re looking at to help you get the right parts.

Generally, when measuring engine components, you would use the proper micrometers and measure to the .0001 inch. However, you can identify components with a simple .001 caliper, as we’ll show here. Plus, it’s a lot easier to carry a caliper with you, than a 0- to 6-inch mic set. To demonstrate, we’re going to go through and measure these “unknown” components from JE Pistons and SCAT Enterprises that came out of one of our other editor’s semi-mystery engines that he recently pulled apart.

If you can identify a part number and a serial number, you might be able to get specs that way. JE has the ability to look up this combination and gave us some good information about the parts. However, we still measured everything because a lot can happen between it leaving the factory and when you run across it.

Identifying Pistons

To some, the idea of buying a used piston is akin to buying used underpants, but there are a lot of pistons on the market that have plenty of life left in them. The key is to make sure you know what you are looking at and for. The primary measurement for all pistons is the bore size they work with, or their diameter. This can be a little bit tricky and a little bit confusing if you aren’t familiar with measuring pistons.

You see, most pistons aren’t perfectly round, and the crown, which is the spot most would think to measure, isn’t where you measure a piston’s diameter. Each manufacturer will specify an exact location of the datum point, but in general, it’s 90 degrees opposite of the wrist pin, about half an inch up from the bottom of the skirt. If in doubt, you can measure various points above and below that half-inch mark to find the largest point, but it will always be 90 degrees opposite of the wrist pin axis.

Identifying pistons

The datum line for JE pistons is .500-inch above the bottom of the skirt, 90 degrees from the wrist pin. So we Sharpied the area and then scribed a line exactly 0.500 inch up.

Now, the second tricky part of the diameter measurement is that it won’t match your bore size exactly. You have to factor in piston-to-wall clearance. Different piston materials will call for different clearances, so the actual measurement related to a given bore size will vary. Knowing these specs is crucial if you are trying to fit an already finished bore. There’s a little more leeway if you haven’t done the machine work yet, but you still need to know that there is a variance there.

For example, say you were looking for pistons to fit your 4.030-inch bore. If you were looking for a set of Hypereutectic pistons, you’d want a piston that measures in at 4.028 to 4.0285 to achieve the recommended .0015- to .0020-inch clearance. Conversely, if you were looking for a 2618 piston for that same bore size, you’d want a piston that measures more closely to 4.025 inches. If you didn’t account for piston-to-wall clearance in those measurements, and you threw a caliper on a set of pistons at a yard sale and saw 4.025, you might pass them up thinking they weren’t the right size for your project.

Placing the jaws at the datum point for both lines we got 4.025 inches. While that’s not accurate enough to measure piston-to-wall clearance, it’s accurate enough to say that these 2618 pistons are for a 4.030 bore.

Beyond Bore Size

The next thing to measure is the wrist pin size. Usually, piston sets will come with wrist pins, so they will be easy to rough measure – just throw a caliper on them and that will tell you what their nominal size is so that you can match them to your connecting rod. Also, look for a marking showing the wall-thickness of the wrist pin, or toss the caliper on it. That spec can be important to your build.

If the wrist pins aren’t included, you’ll want to rough measure the diameter of the wrist pin bore of the piston, again, to make sure they match your rods. If, for some reason, you are looking at wrist pins by themselves, make sure you measure the pin’s length as well, as that can vary from piston to piston, in some designs. If you need a .927-inch diameter 2.500-inch long pin, a 2.750-inch long wrist pin won’t do you much good.

Finding a part number on the wrist pin is the easiest way to identify them. However, measuring OD and length, along with wall thickness is easy enough with a set of calipers and will get you plenty close to identify them.

Next, we’ll need to determine the ring package. For rough measurement in a pinch, you can use the inside jaws on your caliper, but for more precise measurements, you’ll want to use pin gauges, feeler gauges, or an inside mic. Not only do you want to measure the size of the top, second, and oil ring grooves, you’ll want to measure, or at least pay attention to their spacing and location on the piston, which might be a concern for your combination.

You’ll also want to note the compression height of the piston — the distance between the center of the wrist pin bore and the crown of the piston. This measurement, combined with your crankshaft’s stroke and connecting rod length will determine the piston’s location in the bore at TDC. If you’re matching to a set of existing rods and crank, this will be incredibly important.

If you have the rings on the pistons, measuring the ring pack is straightforward (left). However, if they are bare pistons, you’ll need to measure the ring grooves themselves. Calipers will get you in the ballpark, but a set of pin gauges or feeler gauges would be much finer and could identify any wear more easily.

If you’re fitting the rest of the combo around the pistons you got for a smoking deal, you have a little more flexibility here. However, you also need to consider the application as well. If you are going to be feeding tons of boost to the engine, you don’t want a piston with an exceptionally small compression height. Conversely, if you’re looking to turn significant RPM with the engine, you don’t want a huge, heavy slug in there.

The last area you need to pay attention to is the crown of the piston. The first thing is the valve-relief arrangement. Some pistons have valve reliefs designed for the valve angles of specific cylinder heads, to the exclusion of other, potentially more standard valve layouts. The second thing to pay attention to is the dome volume. The three main configurations are flat top, dome, and dish (or reverse dome) pistons.

measuring compression height

The compression height of a piston is a very important spec. By measuring from the crown to the top of the wrist pin bore, and then adding half the diameter of the wrist pin, you get the compression height. Compression height plus rod length, plus half of the crank stroke, subtracted from your block’s deck height will tell you whether the piston sits in or out of the hole.

As the name suggests, a flat top piston is flat, with a 0cc volume (you will want to account for the volume of any valve reliefs present, however). A dome piston is one that has material above the crown, designed to reduce the combustion area and raise compression. A dish piston is the opposite of a dome piston, where there is a void in the crown of the piston designed to increase the combustion volume and lower the compression ratio.

Measuring the exact dome or dish volume of a piston is important. Normally that information will be supplied by the piston manufacturer, but it can be measured at home. For a dished piston, it’s exactly the same process as CCing a cylinder head. For a dome piston, it’s the same process with a little extra math involved, where you calculate the theoretical volume of a cylinder of fluid, and then subtract the actual measured volume. The difference is the volume displaced by the piston’s dome.

CCing a dished piston was quite easy in this case, since the valve relief didn’t break the seal. Measuring dome volume is a little trickier, but very similar. This piston came out to be a 35.8cc dish. Quick math says that these components, with a 4.100-inch stroke crank, would come in right about 8.8:1 compression. Makes sense for the era this engine was originally built.

Measuring Unknown Rods

Moving on to the connecting rods, there are definitely fewer measurements to take, but they are just as crucial. You aren’t going to be able to determine the material just by looking at the rod, but you can determine what rod shape it is, as well as whether it’s a press-fit rod or has a free-floating brass bushing in it.

A rod’s length is actually a measurement from the center of the wrist pin to the center of the crank pin. In order to calculate that, you can add half of the wrist pin diameter (since we know it from above), a measurement of the rod main section (left image) and then half of the big end diameter (center image). As long as you take both the big end and body length measurements either with or without the bearing, you’ll get the right rod length. Notice in the photo on the right that there is a measurement with a bearing. That gives us the crank journal diameter.

What you can and will need to measure to identify the rod are the two holes in the rod, and the distance between them. The first two are relatively straightforward. Using the inside jaws of a caliper, you can get a fairly accurate idea of the big end (crank pin) diameter and the small end (wrist pin) diameter. The next critical component requires a little bit of math to get.

Chances are you’ll be using a six-inch caliper, which means you won’t have the reach to measure everything in one shot and that’s OK. What you will do is measure from the top of the rod journal housing to the bottom of the wrist pin hole. You will then combine that number with half of the wrist pin diameter and half of the rod journal diameter. That will give you the center-to-center length of your connecting rod.

Luckily these rod bolt tell us almost everything we need to know: Bolt manufacturer, bolt material, and rod manufacturer. We still need to measure to find the bolt’s diameter.

The next parameter isn’t necessarily critical to fitment, but is important to performance, and that is rod bolt diameter. Simply put the caliper on the rod bolt and find the diameter. Seems simple, but if we didn’t include it, invariably someone would point out that we didn’t address the rod bolts.

And that’s it. With all those measurements you will be able to quantify anything without a part number, that you need to identify. However, that does bring up the point, that the first thing you should look for on the mystery parts is a manufacturer and a part or serial number. Some manufacturers will be able to give you an entire suite of data based on those numbers alone. Of course, measuring is the most accurate method, since a lot of things can happen once the parts leave the warehouse. They are used, after all.

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The Advantages Of Running Thinner Piston Rings

The quest for more engine efficiency has auto manufacturers adopting thinner rings for greater efficiency when it comes to the family sedan. MAHLE has also embraced this technology, and much more in its motorsports division.

MAHLE Motorsports adopted a new thinner ring technology for performance and racing applications a few years back. The next stage for MAHLE is to educate racers about how these unique rings function and spell out the benefits for their next engine project.

mahle motorsports, piston, piston ring

This side-by-side example of piston designs compares a 1.5mm, 1.5mm, and 3.0mm ring pack (left) beside a 1.0mm, 1.0mm, and 2.0mm ring pack MAHLE cinches up the ring pack with thinner rings, versus leaving the ring grooves in the same location as they would with thicker rings.

We asked Joe Maylish, program manager for the MAHLE North American motorsports division, if material advancements sparked the new narrow rings compared to the thicker rings that have been the norm in the high-performance world for many years. His response is, “Yes, and more.”

Materials And Manufacturing Techniques

“Material is one of the factors,” says Maylish. “MAHLE produces a huge volume of piston rings per year for automotive manufacturers and other applications. The volume of specialized raw materials we use with rings on the OEM side allows us to also engineer and manufacture effective rings for motorsports with an extension of that cutting-edge technology.”

Typically, piston rings can be constructed with different raw materials such as alloys of cast iron and varied steel materials, along with a variety of coatings on the ring face, like gas-nitriding, adding wear resistance to the face of a ring.

mahle motorsport, piston, piston rings, mahle piston              rings

MAHLE is a well-regarded supplier of coated pistons for motorsports. Their Power Pak piston sets have the option of their “thin ring” technology for performance and racing enthusiasts.

Engineers at MAHLE have developed a 1mm top compression ring , 1mm second compression ring , and a 2mm oil control ring assembly pack that minimizes friction and maximizes sealing between the rings and your engine’s cylinder walls.

“Few would argue against the ability of thinner rings to free up horsepower in the right application,” states Maylish. “The typical concern from the racing world is usually first if they will last, and second, are they worth it? So, we asked our engineering team these questions to be able to convey answers to the racers.”

A 1.0mm compression ring can have up to 50-percent less mass compared to 1/16-inch rings. That equals a 50-percent reduction in the inertial force on that individual ring, plus an increased ring-to-piston groove seal.  

Durability

The modern ring pack is much more than just “thin.” In a departure from the typical materials, MAHLE’s metallurgical engineering advancements for these thinner ring packs rely on high-strength steel alloys. MAHLE’s new steel creates a ring far more durable than any cast-iron or ductile-iron option, which achieves proper sealing, thinner size, and less wear in motorsports applications.

The E9254 chrome-silicon steel used in the 1mm top ring successfully minimizes friction and is 35-percent stronger than any cast- or ductile-iron option. With this improved steel comes the ability to produce thinner rings that match the strength of thicker iron rings. The chrome silicon steel contains metallurgical advantages. The materials allow it to achieve ultra-flat ring flanks and a precision finish without machining damage. These two materials also maximize cuff resistance and ring-to-piston sealing.

Less tension by these rings throughout all four strokes of the engine results in less wear on the face of the rings, less drag on the rotating assembly, and less wear on the cylinder walls. – Joe Maylish, Mahle Motorsport

Reduced reciprocating mass is another strong point of the ring. With less mass, the piston and ring can travel up and down faster with higher RPM because of the lessened inertia points at the top and bottom dead center. According to Maylish, at these inertial points, this weight reduction can reduce or eliminate what is called “ring flutter,” which can decrease the ring-to-piston groove seal.

“Granted, you can apply these better materials to any size rings, but that will not overcome the differences in the cross-sectional area with the thinner rings,” Maylish says. “Those smaller dimensions make the rings lighter and more conformable.”

Maylish adds, “This means you can design rings with less radial tension to achieve the same or better combustion gas sealing than a thicker ring. Furthermore, less tension throughout all four strokes of the engine results in less wear on the face of the rings, and less wear on the cylinder walls.”

Steel is also a better conductor of heat and can withstand a longer duration of high-temperature operation without concern for the rings losing tension.

The PowerPak piston line from MAHLE Motorsport offer a long list of included features that were once reserved as options or supplied by separate companies. Off the shelf, these pistons feature full crown machining and coated crowns and skirts. Now, the PowerPak piston sets are available with this new ring technology.

Ring Face Coating

The top ring in the 1.0, 1.0, and 2.0mm pack includes MAHLE’s patented HV385 thermal spray process. This coating is applied to the face of the top ring to improve bond strength of the 9254 steel underneath, as well as durability, and scuff resistance.

“This sprayed material actually becomes embedded into the top ring,” Maylish discloses. “The material is applied through a supersonic, thermal spray process with a liquid-oxygen-powered gun. The HV385 material impregnates itself into the ring face.”

Ring Tension

The fundamentals of all ring designs call for the ring to be formed into a larger diameter than the mating cylinder bore. When installed, the compressed ring tries to expand to its natural diameter and pushes against the cylinder wall; that is called “tension.”

“The conformity of the steel material means you can design rings with less radial tension to achieve the same or better combustion gas sealing than a thicker ring,” Maylish explains. “Older ring designs rely on a comparative ‘brute’ tension force for piston sealing.”

MAHLE’s thermal spraying consists of fine droplets of HV385 material exposed to high temperature and sprayed with supersonic velocity into the face of the top ring made of 9254 steel. Electric or manual ring filing procedures for setting your instructed ring gaps use traditional methods.

The second 1.0mm ring is a reverse-twist taper-faced steel, and the oil rings are standard-tension oil control rings, all with a specific tension designed into them.  

Optimizing Seal

The engine bore is not perfectly round for any engine under power. The stresses on the bore — mechanical loading, deformation, and high temperatures — distort the bores. This distortion is typically measured in microns. It sounds minute, but those stressed bore shapes allow cylinder pressure to escape the combustion area past the rings.

MAHLE pioneered computer simulation software and other development tools that successfully minimized friction without sacrificing sealing capabilities. Maylish states, “These rings’ ability to conform to the cylinder walls increased measurable horsepower gains on the dynamometer during our development process. Furthermore, less tension throughout all four strokes of the engine results in less wear on the face of the rings and less wear on the cylinder walls.”

The PowerPak piston sets from MAHLE Motorsports are available with traditionally dimensioned ring sets or the newer 1.0, 1.0, and 2.0mm options. Here is your typical big-block Chevy piston set with the thin ring option.

Strengthen The Piston

These thinner ring sets also allow the MAHLE engineers to develop new piston designs with shorter ring packs that eliminate the wrist pin bore from intersecting the oil ring groove. This clearance is a big plus for many small-block and LS engines. Now, the pin bore has space to sit below the oil ring groove, eliminating the need for support rails, which improves overall piston strength.

New technology for racing is on a constant quest for stronger, lighter, and better-performing designs. There is no question that these thinner MAHLE rings are an effective addition to the motorsports world, since they meet those criteria.

Not just a fad diet, the results from MAHLE’s dyno research and scores of other independent tests by performance engine builders cite the multiple benefits of piston and ring assemblies to not just be smaller, but to add a critical conformity between the rings and the cylinder wall. This “diet” provides a better seal to prevent compression gases from escaping around the piston, the biggest single job rings have.

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Seal The Deal: Total Seal’s Gas-Ported Piston Rings Seal Everything

Research has proven how critical piston rings are to internal combustion engines. The rings are the primary source of friction inside the engine, which we know causes a loss of power and increases heat. But, for the pressure of compression and, to a greater extent, the expansion created by ignition when the air/fuel mixture burns and creates peak cylinder pressure, the rings are what keep that goodness sealed up atop the piston. It’s a high-stress environment and the piston ring is dealing with an extreme compromise.

On one hand, we want the ring to seal completely and contain all of the energy and pressure up in the combustion chamber where it belongs. This way, it can use its pressure to force the piston down the bore and turn the crankshaft with maximum potential power. On the other hand, we want to minimize the friction between the piston ring and the cylinder wall, so we don’t waste any of that precious power we just created to overcome frictional losses. What can we do to minimize this compromise?

First, we can make the piston rings as thin as possible. This minimizes their “footprint” on the cylinder wall so friction is lessened. We want to make the ring as thin as possible while making sure it still can seal effectively. We can run a thinner ring if we know it has sufficient pressure to hold it firmly against the cylinder wall.

The lateral grooves machined into the top face of the piston ring allow combustion gasses to make their way behind the top ring, and exert force outward on the ring, making for a better seal, with no holes drilled in the pistons themselves.

Using Combustion Pressure To Seal

Creative engineers discovered that they could borrow a little cylinder pressure from the engine to assist the rings in sealing to the bore by drilling small holes down through the top of the piston to the space behind the ring — this is called gas-porting a piston. This way, the ring seal would improve dramatically when cylinder pressure was high, but the tension would drop when that cylinder pressure was no longer present (at the bottom of the power stroke) and ring resistance against the cylinder bore wall could be minimized on the exhaust stroke. This gas porting has been a proven upgrade for decades.

This is a very common modification on race-only engines that get rebuilt often, but because the holes drilled through the deck of the piston are so small, they get clogged up quickly in street engines where more carbon is present and rebuilds are infrequent. Luckily, the team at Total Seal wasn’t content to leave the idea alone. They realized how a top ring could be given “ports” itself, allowing cylinder pressure to come in behind it from the top and accomplish the same thing as the drilled holes. But, would gas-ported piston rings remain strong enough not to twist? Could it still seal effectively against the cylinder wall with less mass, being a lighter-weight ring?

Total Seal gas-ported piston rings

Total Seal can gas-port almost any ring in their catalog, except gas-nitrided rings. So whatever you’re running for a piston ring, there’s a gas-ported ring to fit it.

After some research and experimenting, the answers were both yes. We learned that Total Seal not only offers gas-ported piston rings in standard sizes, but can retrofit thinner rings to standard pistons through the use of a special shim in the ring groove to space the ring correctly and support it, and that the rings themselves were carefully crafted to survive long-term in this angry environment with their special task at hand.

We spoke with Keith Jones at Total Seal, and he shared with us how it’s done.“We have groove spacers to reduce the axial height, which means we can put a nice thin ring in a thick groove. We make these spacers in .016-inch, .030-inch, and .046-inch heights. But not in all bore sizes. As far as the shim to fill in the back clearance behind the ring, we offer .035-inch x .014-inch (axial and radial), .055-inch x .016-inch, and .070-inch x .014-inch, depending upon the height of the ring groove. Ideally, one wants about .005-inch-.010-inch back clearance behind the ported ring. This small amount of space gas-loads quickly, and reduces excess crevice volume, which can affect ring seal,” Jones explains. 

By using spacers for both the radial and axial widths, a much thinner ring can be utilized in a piston with traditionally sized ring grooves.

“We can gas-port about any ring except a gas nitride part, so the coatings can be about anything from Molybdenum, to hard chrome, to a wide range of PVD coatings. Pretty much whatever the customer might want for a gas-ported ring, we can deliver it.”

Gas-Ported Piston Rings — All Of The Benefits, None Of The Drawbacks

Naturally, we wanted to get a look at these new gas-ported piston rings and put them to work inside an engine that could really benefit from their design. We were screwing together a pretty typical 383ci small-block Chevy for a dedicated drag car, so we ordered up a set for its 4.030-inch bores. After we received the rings from Total Seal and examined them closely, we saw how the ports are machined grooves on the top surface of the ring. This allows the pressure from the top of the ring to pass behind it and press the ring outward against the cylinder wall. The bottom surface of the ring is typical; smooth and featureless.

You can see the grooves on this piston aren’t particularly thin. However, we were able to use a thin ring to reduce friction without buying new pistons.

Of course we followed Total Seal’s instructions on installing the shims, and then the rings over them. The ring end gaps were hand-filed to specifications, which were typical. We went with .018-inch on the top ring, and .020-inch on the second. Once we were sure that we’d done everything correctly, we continued with the assembly of the engine as we normally would. We used Total Seal’s “Quick Seat” powdered lube product on the cylinder walls to ensure proper break-in for the new rings.

The engine performed as expected on the dyno, making good power and pulling strong to 7,000 rpm. The post-dyno leak-down test showed the gas-ported piston rings were sealing well, as they should. This engine will be pulling a ’39 Ford down the quarter-mile for the foreseeable future, delivering years of 9-second passes in a reliable, durable, and powerful 650-horsepower package. We’re confident this is a great test for the new ported rings, since we don’t anticipate tearing the engine down until it’s worn out, which shouldn’t be for a very long time.

Gas-ported rings are also available in Total Seal’s signature “Gapless” design as well. On the left, you can see the ported top ring and the gapless rail separately. On the right, you can see the two fitted together. With the rings staggered 180 degrees from one another, you have a gapless ring that seals like a gas-ported ring.

Personally, I am in awe of the current state of race engine technology available to weekend enthusiasts like this. To have an engine capable of making this kind of power that requires a minimal amount of maintenance means we won’t have to worry about it on race day. We can focus our time and money on other parts of the car where improvements can still be made.

Thanks to the engineering being accomplished at Total Seal and other companies like them, we can truly enjoy our race cars (and trucks) and make the kind of reliable power that was reserved for those with much higher budgets in the recent past. A special thanks go out to Keith Jones for his guidance and assistance, making sure we got the right parts and installed them correctly.

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Why You Need A Fuel Pump Voltage Booster

You can buy a car off the showroom floor from General Motors, Ford, and Dodge that make a ton of horsepower via forced induction, but what if you want more? Well, one of the first things you’ll need to do is address the fuel system, and there’s a simple way to do that with a fuel pump voltage booster. We talk with Chris Johnson from JMS to learn more about fuel pump voltage boosters.

It’s almost criminal how easy it is to crank up the horsepower on a boosted modern muscle car with a pully change and a few other modifications. The problem is the OEM fuel system isn’t designed to handle the additional horsepower as it sits, but that’s where the fuel pump voltage booster comes in. A fuel pump voltage booster increases the amount of voltage provided to the fuel pump, therefore, allowing it to spin faster, and keep up with the increased demands of the fuel system.

Chris Johnson from JMS explains how one of these fuel pump voltage boosters works.

“These boosters, like our FuelMax unit, can increase the voltage from 14.4 volts up to 22 volts. The normal single or dual pump setup can increase fuel volume by over 50 percent with that voltage booster alone, without having to buy an entire fuel system. The majority of the uses are with the stock fuel pumps, so the owner doesn’t need to put a bigger pump in the car to achieve their horsepower goals.”

A fuel pump voltage booster is actually a pretty simple modification to install on a boosted vehicle. You don’t have to cut the vehicle up or make any big changes to its structure. The fuel pump voltage booster system just needs to be wired into the OEM system and it’s triggered by a Hobbs switch when it sees boost.

“Spinning the pump harder isn’t an issue because it isn’t happening all the time. If you’re not in boost, the voltage booster isn’t going to be activated to spin the pump harder than it normally would. It only turns on when you program it to. The pump is also in fuel in the stock location inside the tank, so it’s being cooled by that fuel. It’s an on-demand system. It’s pedal activated and is regulated, so it activates almost like a secondary fuel pump,” Johnson explains.

JMS has worked hard to make the FuelMax a user-friendly unit.

“The FuelMax uses OE style connectors because nobody wants to take an expensive car and start cutting wires. The simplicity of taking it out of the box and plugging it in is a big advantage. The normal person at home could install this at home, they just need some basic skills. The FuelMax can also be mounted just about anywhere in the vehicle, so that adds a lot of convenience. These units are available for the Hellcat, Challenger, TRX truck, Mustang, and Camaro,” Johnson states.

You can pick up a plug-and-play FuelMax EZ for the GT350 and GT500 Mustangs. These units will support up to 1,000 horsepower with a single fuel pump, and up to 1,300 horsepower on a dual fuel pump system. These will work with either a 12-volt or 16-volt system too.

If you want to learn more about fuel pump voltage boosters and see what JMS has to offer you can visit the company’s website right here.

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Top Ring Gap Theories Explained By Wiseco Pistons

 

 

 

 
 

The ring gap topic is critical to engine performance and longevity. Nickolaus DiBlasi, global product manager at Race Winning Brands, explains many points based on the top compression ring and its gap specifications.

 

Arguably one of the most opinionated assembly processes when whipping up your next racing engine project is ring gap, and most to the point, the top compression ring. Race Winning Brands and their company, Wiseco Pistons, is known for its vast array of motorsport pistons, but many racers rely on their related piston rings with success, as well.

What Exactly Is Ring Gap?

“The top ring sees the most heat,” DiBlasi points out. “With that in mind, the smaller the gap, the less opportunity there is for combustion chamber pressure to make its way past the first ring. The greater contact the top ring has with the cylinder wall, the better heat transfers to the cylinder and onto the water jackets.”

Not Too Tight

The theory of minimum possible piston ring gap has limits, especially when you factor the thermal expansion of materials onto the overall gap theories. As the block, piston, and rings all heat up, they change dimensions ever so slightly and at different rates. DiBlasi takes it down to the molecular level.

“Since the top ring will see most of the heat, they expand quite a bit,” DiBlasi says. “The gap you create in the top ring is to accommodate the maximum expansion you anticipate the top ring requiring.

If the top ring is gapped too small, when it expands, the ends will run into themselves. This added force introduces even more heat, and the rings expand further. Once that happens, catastrophic failure will occur rapidly, as it is a continuous cycle of more heat, more outward pressure, and with nowhere for the ring to expand.

Piston ring gap theory is critical to ensure that the top ring is not bypassing compression, but not expanding so much that the ends run into each other. — Nickolaus DiBlasi, Wiseco

Read The Manufacturers Specifications

The best way to prevent this kind of runaway destruction is to pay attention to the information provided with your new Wiseco pistons and rings. DiBlasi adds, “We have outlined our recommendations that are included with pistons. These are also available in our catalogs and website.”

Setting ring gaps can be a slow process, but with experience, you can get a feel for what each ring will need and get closer to the finished spec quicker. Remember only to file one end of the ring and avoid damaging any coating the rings may have.

Ring manufacturers know their individual ring materials and their expansion properties down to the molecular level; they understand their exact expansion rates to factor into a specific gap. Following their individual gap specifications are the best bet for a ring gap that is just the right size.

 

 

 

 

 

 

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Turbo Failure. Here’s A few Tips To Prevent One

Idoubt many people have given much thought as to how and when the turbocharger was born. I won’t bore you with the details but know that it happened way back in the early 1900s. Once it was discovered how much additional power a turbo can provide, their applications for use continually grew.  You can imagine the number of design changes they have seen over the years, and they are still undergoing as time creeps along. Revisions typically mean improvements in one way or another. However, just like diesel engines, some designs have proven better than others.

We decided to shed some light on some common ways a turbo can fail and what can be done to prevent that failure. If you would like to protect an expensive and vital engine component then read on as Nate Brekken, co-owner of Strictly Diesel disassembles a pair of turbos for inspection.

turbo

Pictured on the left is a Garrett VGT turbocharger from a 6.0-liter Power Stroke. On the right is a Garrett fixed vane turbocharger from a 7.3-liter Power Stroke. Both units will be disassembled and inspected for their failures below.

Looking at how a turbo operates, they’re pretty simple. Exhaust pressure is used to spin the turbine wheel which causes the compressor wheel to spin at the same speed. The compressor wheel is used to pull air through the air filter and then into the compressor housing. The air is then compressed, sent through the intake manifold, and then into the engine. As you zoom in closer, things get much more complicated and sensitive.

They’re The Same, But Different

There are two main categories of turbos, and while sharing many of the same components, they have some major differences as well. The first and more traditional turbo design is referred to as a fixed vane or fixed geometry turbocharger. These were found in diesel engines before they were equipped with emissions equipment like EGR valves and coolers. This style of turbo does not suffer from soot buildup on the exhaust side since the only moving part is the turbine wheel. They do not have components like vane actuators or vane position sensors, unison rings, vanes, or vane cages. For that reason, many feel these are more reliable units.

The second design, which you’ll find on modern diesel engines, is referred to as a variable vane turbocharger (VVT) or a variable geometry turbocharger (VGT). These two are essentially the same thing and you’ll commonly hear them referred to as one or another. Both of them have either individual vanes or a vane cage inside of the exhaust housing that opens or closes to alter the exhaust housing’s Area over Radius (A/R) ratio. By creating a lower effective A/R ratio, the vanes help the turbo build boost sooner. By “opening up” the vanes, this creates a larger effective A/R ratio allowing for better top-end performance. They offer many other benefits and are almost a necessity with strict emission requirements. Two common examples of these include Garrett turbochargers that have vanes that open or close whereas Holset uses a cage that moves in and out.

Failure On The Exhaust Side

Through normal driving, soot will flow through the exhaust housing, and over time it can build up, leading to problems. Typically, this is seen in trucks that live a very easy life with little to no towing or hauling, and not a lot of heat being generated. Although this type of usage may net better fuel economy, the downside is problems are created in the vanes. If the vanes don’t see a full range of frequent movement or heat, then soot deposits can build up and block their range of motion and cause a turbo failure. In some cases, it can cause the vanes, unison ring, or cage to seize in one position. Your truck will recognize this very quickly and set a check engine light.

The unison ring is shown on the far left. This is what moves all of the vanes simultaneously (right). The middle picture shows the pin which swivels to open or close the vanes and is controlled by the actuator.

Depending on the position they are stuck will cause either a lack of low-end or top-end power. When this happens, it might be possible to remove and clean the turbo, but depending on internal wear or its age and mileage, it may be best to have it replaced. More-than-normal soot build-up can however be caused by other things like boost leaks, exhaust leaks before the turbo, or tuning with a low focus on smoke control. The good news is, there are some ways to help prevent this. Keeping the vanes moving is the goal, which can be done by enjoying some spirited acceleration runs, using the turbo brake, and of course, making sure the engine is mechanically sound. Towing will help this situation as well since the vanes will be cycling back and forth.

Death By Fire

Since turbos use exhaust flow to function, they see a tremendous amount of heat. For those of you who monitor exhaust gas temperatures (EGTs) and tow heavy loads, you’ve seen firsthand how this number impacts your cooling system. EGTs can also impact your engine’s turbo, and this is frequently forgotten. High temperatures can result in damage to the turbine wheel and can be seen by an orange peel appearance or rippling on the fins of the turbine. Another indicator is when the metal has folded over and melted away. Melting metal off of the turbine wheel may seem like a stretch, but when metal is missing and there’s no evidence of contact inside the exhaust housing it’s pretty clear what happened.

Metal is a great conductor of heat, so it’s easy for it to transfer into the bearings. Turbochargers use a thrust bearing to limit how far the rotating assembly can move from side to side. The journal bearings allow the rotating assembly to spin, and these are generally brass bearings that ride on the center of the shaft. As heat makes its way in, signs of it can be seen by discolored metal components. You may see where brass material from the bearings has transferred onto the shaft, or created darker areas that can appear black and burnt or blue in color. If EGTs are too high for too long, this can begin to melt the bearings and plug the oiling holes built into them. If there’s no film of oil to keep them lubricated, the wheel may be difficult to spin by hand or it could seize and not spin at all.

Turbo failure

It’s apparent these vanes have made contact with the housing.

This is why monitoring exhaust temperature is so important. Pyrometers allow you to see, in real-time, the heat being generated which can be an indicator of how hard you’re pushing the turbocharger. There are a lot of factors that cause high EGTs, but here are some tips. First, don’t lug the engine when towing heavy loads. Even though the engine may have the power to run with low boost pressure and move the load, low airflow means higher EGTs. Keeping the engine RPM up will raise boost, increasing airflow into the engine. This in turn decreases EGTs. This is not always enough, so you may find yourself having to slow down and downshift. Moving a loaded trailer shaped like a brick, with a headwind may prove too much to maintain speed with the rest of traffic. It’s best to make the engine and turbo work, just not past its efficiency range to the point of failure.

Bearings Prefer Clean Oil

As mentioned above, bearings can fail due to heat. They can also fail due to a lack of lubrication or contamination. When a turbo fails and is disassembled, the bearings can paint a clear picture. If there is any foreign debris in the engine oil, it may plug the oil passages starving it of oil. This contamination could also make its way into the bearings and cause scarring or other wear marks. Excessive wear to the bearings can cause the rotating assembly to be out of balance or have excessive lateral or vertical movement. Eventually, it can be severe enough to allow one or both of the wheels to contact the housing.

The wear on the thrust bearing to the left is evident by the rough edges and the gap between the two parts. This was allowing enough side-to-side movement for the turbine wheel to contact the exhaust housing. The journal bearings on the right have excessive scarring from contaminants in the engine oil. Also notice the fuzzy material on them, that’s from a red shop rag used to wipe them off. Remember that when using those to clean small components like these if they’ll be reused.

Good maintenance is the key to preventing turbo failure. Oil change interval recommendations vary from one person or manufacturer to the next. Unless you’re running a bypass filter or fine-mesh filter, we don’t recommend extended drain intervals. It’s personal preference and it’s your truck so do as you please, but oil changes every 5,000 miles are much less expensive than replacing an engine. Turbos aren’t cheap either. Another great piece of insurance is a magnet around the oil filter. Filtermag makes curved magnets that stick to the side of the filter and work very well at trapping metal and preventing it from circulating throughout the oiling system. Whatever you do, make it a point to keep clean oil in your engine to keep it and the turbo healthy.

Filters And Air Intakes

Just like needing clean oil, your turbo needs clean air — and lots of it. A few different problems exist around filters and air intakes. The obvious is poor air filtration. Any dust or debris that makes its way through the filter will contact the compressor wheel. This will have a sandblasting effect and over time it will wear away the outer edges of the wheel. Upgraded billet wheels have a softer metal than factory ones and can be more easily damaged. This can lead to an unbalanced assembly as well as reduce the air it pulls through the intake. Less air means reduced efficiency and circles back to increased EGTs. The next problem is air restriction most commonly seen by dirty and plugged air filters. Trucks with performance tuning that run a factory air filter can run into this as well. A restrictive filter can cause an overspeed situation taking it beyond its operating limits. This force can overcome the film of oil on the thrust bearing and cause the rotating assembly to be pulled far enough in a direction allowing it to contact the housing.

Plugged and deformed, this filter was doing more harm than good

Aftermarket air intakes generally improve airflow over the stock setup, but make sure you choose one that uses a quality filter. Not all are created equal. When the right engineering has gone into a kit you’ll find ISO test results, intake temperatures drop, and CFM improvements compared to a stock intake. If you decide to run a larger-than-stock turbocharger then plan on ditching the factory intake to allow your turbo to breathe in a lot of clean air.

Overall, turbochargers can be very reliable units as long as they’re properly cared for. This can come in the form of changing your driving habits, being proactive with maintenance, using quality parts, and making sure you have the right setup for your use and your turbocharger. Remember that turbos don’t normally fail on their own so don’t shoot the messenger.