Turbocharged 1,500-Horsepower 6.7L Cummins Engine - Engine Builder Magazine

Turbocharged 1,500-Horsepower 6.7L Cummins Engine

With a shop name like Dragon's Lair Garage, you know what comes out of there has to be cool. Case in point, shop owner Karry Latropoulos' turbocharged and nitrous-boosted 6.7L Cummins is pretty awesome! Check it out.

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Karry Latropoulos and his brother have been invested in automotive for the better part of their lives and have completed tons of restoration projects and custom builds. In all that time, diesel wasn’t something they got into, until recently when they finished their first diesel build at their shop, Dragon’s Lair Garage. With a name like that, you know it had to be something cool they cooked up.

The Rolling Meadows, IL-based shop is primarily a restoration shop, according to Latropoulos, who says the shop handles one-off builds and frame restorations along with metal fabrication work and engine modifications. The diesel build strays away from their usual work, but it’s still rather impressive.

For about two years now, they’ve been modifying a 2014 Ram 2500 that weighs around 7,400 lbs. Powering the beast of a truck is a mighty, turbocharged 6.7L Cummins engine.

“It’s got a ton of power to it,” Latropoulos says. “I’ve had it dyno’d four times and every time it kept spinning. On fuel only, I believe we made 1,440 horsepower, so realistically with the new turbo setup we should be around 1,500 or 1,600. Spraying it with nitrous, it’ll be well over 2,000.”

The engine has a true 6.7L displacement complete with 24 valves and a ported and polished 6.7L crank, despite many engines built to this power level being scaled down to a 5.9L crank. The block was honed at a separate shop and drilled out for 14mm main studs.

A Wagler Competition girdle and main caps work to support the bottom end and Wagler connecting rods connect the crank to coated MAHLE pistons. Ported and polished Hamilton race heads and oversized valves allow for increased flow.

The build also features 110-lb. valve springs, XDP billet valve bridges, Hamilton 12mm pushrods, 1.5″ tappets and rocker arms with DLC-coated trunnion shafts, a Hamilton 188/220 camshaft, a Fluidampr balancer with drill pin and full power retention kit, an electric water pump, Keating Machine billet bolt-in freeze plugs, and a Fleece coolant bypass.

“All the fuel on the truck is S&S,” he says. “It has 350% over injectors with body modifications, an S&S 14mm race pump, their SP 3000 mechanical pump, and a Bean Machine sump in the fuel cell.”

On the air side, Latropoulos’ engine features a T6 competition manfold with a Stainless Diesel “Godfather” S485 96mm non-gated turbo. He also has a Nitrous Express kit and spool jet set up for five kits of nitrous.

“For the new build, I’m either going to keep the turbo the same or put on a GT55R 114m turbo that’s much bigger,” he says.

In the near future, Latropoulos plans on removing the engine from his ’14 Ram and dropping it under the hood of a custom cab that he built. The chopped and stretched tube chassis is going to serve as his next No Prep race truck, and weighing considerably less, the power-to-weight ratio will make for one hell of a quick truck.

Diesel of the Week is sponsored by AMSOIL. If you have an engine you’d like to highlight in this series, please email Engine Builder Editor Greg Jones at [email protected].

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