Power Driven Podcast

Ever heard someone swear a big diesel dyno number has to be fake? On this episode of the Power Driven Podcast, Todd, Will, and Myer take on the dyno slap myth and get into what really separates the guys making serious diesel horsepower from everybody else. Spoiler: it’s not cheating, it’s obsession.

The guys break down why certain people become the go to experts on one Cummins platform, whether that’s a first gen, a VP44 2nd gen Cummins, or a P pump 12 valve Cummins. Seat time on one diesel engine teaches you things no forum post ever will, like a VP44 builder finding real horsepower differences just by swapping ECMs.

You’ll also hear a great 12 valve troubleshooting story from a recent event. A 1995 Dodge Cummins lost its tach and speedometer, and after 40 minutes with a wiring diagram, the culprit turned out to be a pulled fuel pump fuse in the PDC. On a 95, that fuse also feeds the PCM, so pulling it to “delete” a lift pump that was never there killed the computer.

Then the crew gets into diesel dyno strategy and why dyno slapping isn’t real. Myer explains how his Cummins nitrous kits are staged about 200 rpm apart with fuel ramping in over roughly 1,000 rpm. He opens the wastegates ahead of the spray to keep boost and drive pressure in check, and repeatable dyno runs that line up with the math prove the numbers are legit. They also cover how overfueling a big turbo diesel setup cools the exhaust and snuffs the turbo, and how to set up an AFC on a hot 12 valve so it doesn’t hit full fuel too early.

Myer’s 48RE transmission has been a big part of his season at the Ultimate Callout Challenge (UCC), diesel drag racing events, and dyno days. As far as the crew knows, it’s holding more power than anyone has put through a Turbo 400, and the only maintenance on the truck all year has been an oil change. They explain how transmission slip can scatter an engine and why a Bosch ECM that thinks fast enough is worth every dollar over a factory 849.

You’ll also hear why a 6.4 deck plate isn’t automatically the right call over a 6.7, why common rail diesel trucks dominate turbo limited classes like 72 fast, and the small details that win dyno days: chains instead of loose straps, rear lockouts, a spool, a weight rack, and where the tire sits on the roller.

To wrap it up, a listener writes in to settle the EGT versus EGTs debate once and for all.

If you’re into Cummins builds, diesel performance, diesel tuning, and making real horsepower, subscribe on YouTube and follow the Power Driven Podcast on Spotify, Apple Podcasts, or wherever you listen.

Whether you’re chasing your first 1,000 horsepower out of a P pump 12 valve or building a Cummins that can survive serious dyno abuse, the parts and know-how behind this episode are available at PowerDriven.com. 

Shop Power Driven Diesel: https://www.powerdriven.com

Single turbo or compound turbo: which one really makes more horsepower? This episode started with a comment from viewer @V8Lenny (youtube.com/@V8Lenny) claiming a single turbo will always make more power than the same charger run in compounds, so we put that claim up against years of diesel dyno numbers and real Cummins builds.

The conversation starts with results from 12 valve Cummins and 6.7 Cummins common rail diesel trucks. A 98mm charger that made 1100 horsepower as a single made 1500 to 1600 in a compound setup, while an S480 made the same power either way. It also covers why big singles are so hard to tune on a common rail diesel, from snuffing the turbo with too much fuel to adjusting rail pressure and timing so the fuel drives the charger.

From there it gets into turbo science. Diesels have less drive energy than gas engines, which is why sled pull turbos run huge turbine wheels and why high altitude makes everything harder. Compressor efficiency, pulse energy, and interstage cooling all come into play, along with The Godfather, a triple turbo 12 valve that made 2800 horsepower with four stages of densification.

Cylinder head flow is a big part of the picture too. Head flow decides where an engine wants to make peak power, and matching your turbos to the head matters more than chasing RPM.

Testing on the Junker drag truck shows both sides of the single turbo vs twin turbo debate: an S476 single that barely broke 700 on a 5.9 Cummins, an S369 single that beat a set of towing compounds, and a 12v Cummins build where compounds made way more power. The episode also explains why compounds spool better at low RPM and when they don’t.

It wraps with the 72 Fast class pushing near 1500 horsepower on a 72mm turbo and a final verdict on @V8Lenny (youtube.com/@V8Lenny) claim: compressor for compressor, a well tuned single usually wins, but compounds are way easier to tune.

If you want real diesel power talk from guys who run this stuff on the dyno, subscribe to Power Driven Diesel on YouTube and follow the Power Driven Podcast wherever you listen.

Building a big single or a set of compounds? Power Driven Diesel has the parts to back it up.

Aggressor turbos, compound turbo systems, CNC ported cylinder heads, and complete power packages for 12 valve, 24 valve, and common rail Cummins are all available at PowerDriven.com.

Shop Power Driven Diesel: https://powerdriven.com

What happens when an $11,000 VP44 Cummins with a short parts list out tow trucks that cost five times as much? Willard, our 2001 Dodge Ram dually, just pulled a race trailer home from Diesels in the Mountains and held the speed limit up the grades. This episode breaks down why this old 24 valve keeps surprising everybody and what it takes to turn a 25 year old diesel truck into a legit cross country tow rig.

Todd, Will, and Myer walk through the simple build on this 5.9 Cummins with the VP44 injection pump: a 650 horsepower transmission, Power Driven stage two injectors, a turbo upgrade, head studs, intake, and exhaust. On a clean tow tune it pulls hard, makes around 520 wheel horsepower on the top tune, and the EGT control is so good the crew had to verify the gauge with dual pyros on the dyno. They also get honest about the limitations, like the four speed and 3.55 gears making it slow off the line with a heavy trailer compared to a newer six speed truck.

Next they cover the comfort list that turns a fun truck into a real tow truck. That means killing exhaust drone with a better tip and a big straight through muffler, adding an inline four inch exhaust brake that leaves room for compounds later, and why V band connections matter for exhaust brake performance.

Old truck problems get their own fix list too: a leaking heater core, a cracked second gen dash, sound deadening while the interior is out, a turbo silencer ring, a modern radio with a backup camera, better tow mirrors, headlights, and brakes.

The guys also run the numbers. Willard sits around $22,000 all in, with way fewer electrical gremlins than a brand new Ram 2500 that can lock you in the cab on the side of the highway.

Finally, they map out the next stage of this VP44 build: camshaft, ported cylinder head, then turbos, chasing a 700 to 800 horsepower tow truck on a stock VP44 pump. Plus some fun talk about how Willard might stack up against the new 8.3L Duramax in a TFL Truck style towing test.

If you love old Cummins trucks and real diesel performance talk, subscribe on YouTube and follow the Power Driven Podcast on Spotify, Apple Podcasts, or wherever you listen.

The parts that make Willard tow like this are the Power Driven stage two VP44 injectors, the 650 horsepower transmission, and the turbo setup.

If your turbo whistle is wearing on you during long tows, the turbo silencer rings are on the site too. Shop everything mentioned in this episode at PowerDriven.com. Links below.

Shop Power Driven Diesel: https://www.powerdriven.com

A shelf on cylinder head just won the biggest payday in diesel drag racing, and it beat trucks running heads that flow a lot more air. If you think bigger is always better on a race build, this episode of the Power Driven Podcast might make you rethink your whole combo.

Todd, Will, and Myer break down the 72 Fast class in Texas, where first place took home $100,000. Every truck runs the same 72mm VS Racing turbo with zero modifications, weighs at least 6,000 pounds, keeps a factory ECM, and launches off a foot brake against an instant green tree. No nitrous, no water injection, no trans brake. It all comes down to engine building, tuning, and the guy behind the wheel.

Will explains how he ran the numbers on Matthew Parker's 6.7 Cummins and built him a Power Driven Stage 3 diesel cylinder head with the shelf left on. At a 4,000 rpm shift point, the engine only needed about 267 CFM, and the head flowed 261 on the bench. Parker tested it back to back against his old head with the same tune, watched his air fuel ratio go leaner, kept adding fuel, and eventually ran out of CP3 at peak torque. He went on to win Texas after already taking Indy.

The guys also talk about Spencer Shultz, who finished runner up with a head Will reworked after a dyno contest, and why those two trucks were nearly dead even. That opens up a straightforward breakdown of coefficient of discharge, valve size, and airspeed, and why a smaller, efficient port can fill the cylinder better than a big one when everything is sized to your RPM window.

Camshaft selection, two valve versus four valve heads, and why injector placement matters for combustion all come up too. It is the kind of conversation every diesel engine build should start with before anyone orders parts.

To wrap things up, they cover rumored new classes for next season, plans for their own race trucks over the winter, and a 3,503 uncorrected horsepower pull on a SuperFlow dyno that set a record for raw numbers on that machine.

If you are into diesel performance and truck drag racing, subscribe on YouTube and follow the Power Driven Podcast on Spotify, Apple Podcasts, or wherever you listen. Plenty more coming this winter.

The Power Driven Stage 3 cylinder head that carried Matthew Parker to his second straight 72 Fast win is available for your own 6.7 Cummins, along with our full lineup of diesel cylinder heads, engine blocks, and performance parts built and tested in house using real race data. Whether you are building a race truck or a street build that pulls harder where you actually drive it, grab everything mentioned in this episode at PowerDriven.com.

Shop Power Driven Diesel: https://www.powerdriven.com

What does it actually take to keep a Cummins alive past 3,000 horsepower on the dyno? It is not just more fuel and a bigger nitrous shot. This episode breaks down the real engineering behind Myer's second gen common rail race truck and why so many mega power builds scatter before the pull is over.

With Diesels in the Mountains coming up in Utah, Todd, Will, and Myer dig into the torque limit of a factory cast block and why it wants to split right at the cam tunnel. They explain how making the same torque at 6,000 rpm instead of 2,500 turns a tow rig number into a record number, and why dyno correction factor at altitude means the uncorrected number is the one worth comparing.

On the engine side, the guys walk through how a deck plate and a longer rod move the peak cylinder pressure above the factory block, and why they run the sleeves with a loose fit instead of a press fit so the weaker cast iron is not preloaded before the fire ever happens.

For diesel tuning, they cover why nitrous means pulling 10 to 15 degrees of timing compared to a fuel only tune, how injector size changes how precise your injection window has to be, and why floating valves are behind most nitrous dyno blowups. Diesel cylinder pressure at this level is closer to Top Fuel than anything a gas valve manufacturer is used to, which is why Inconel is on the table.

Then it gets into the turbo and nitrous setup. Myer runs four bottles, each on its own feed line, plus three wastegates that open the moment each nitrous kit fires so boost stays in check before it can overshoot. They also talk about undivided turbine housings, running as lean as 50 to 1 on the dyno, and why four bottles is about delivery, not showing off.

The episode wraps with transmission line pressure and how slippage quietly costs hundreds of horsepower, running higher tire pressure with a spool to keep tires from blowing apart, and the dream of a hub dyno power wheelie.

If you learned something, subscribe on YouTube and follow the Power Driven Podcast on your favorite platform so you catch the next one.

From deck plates and sleeves to turbo boots and nitrous components, the parts behind builds like Myer's are the same ones we run and trust every day. Shop everything mentioned in this episode at PowerDriven.com.

Shop Power Driven Diesel: https://www.powerdriven.com