Turbocharged 6.4L Cummins Engine - Engine Builder Magazine

Turbocharged 6.4L Cummins Engine

This 6.4L engine under the hood of Aaron Reynolds' '94 Ram 2500 helped the truck knock off a 5.51 at 136 mph in the eighth mile. Check out the details of the build!

Diesel of the Week is presented by

Tameless Diesel Performance has been serving the Asheville, NC community for 6 years now, providing a variety of quality automotive services. The shop mainly focuses on diesel repair and performance work, but also dabbles in gas applications from time to time, such as LS-based projects.

According to owner Aaron Reynolds, Tameless Diesel runs a four-bay operation with plans to upgrade soon to a 15,000 sq.-ft. facility. Even now, the shop has more than enough work coming in. With a chassis dynamometer in-house, the team is able to complete a range of tuning work for their customers as well.

Photo by Cheyenne Alexx

“We actually have the same chassis dyno that Ryan Milliken has, so we do a lot of tuning with him,” Reynolds says. “But, aside from that, we do all three of the Cummins, Powerstroke and Duramax platforms – old and new. Occasionally, we’ll work on some heavy-duty stuff like Class-A trucks, but we mainly focus on pickups.”

Reynolds began his foray into the diesel world in 2008, when he purchased his first truck. Back then, he was building houses during the day and working on diesels at night. Now, he’s flipped businesses and builds trucks during the day and builds houses on the side. That switch gave him more time to work on performance builds, like his current race truck – a ’94 Dodge Ram 2500 with a turbocharged 6.7L Cummins engine.

The truck was originally bought from a friend, and then outfitted with a ton of new upgrades to regain its former glory. Reynolds said this is one of the “OG” Pro Street trucks that hit the track back when diesel racing boomed in the late 2000s.

The first step was dropping a new engine under the hood, and Reynolds settled on a 6.4L powerplant based off a 6.7L block. The Fleece Performance motor formerly sat under the hood of Ryan Milliken’s “Mini-Wheat” truck, until the long block was transferred to Reynold’s new ride.

“It’s a Fleece block with all their modifications, and obviously it’s sleeved and has their racing head on it. There’s a Beans Machine triple CP3 front cover on it that runs injection pumps and stuff, and a Hamilton camshaft.”

Wagler connecting rods and Diamond pistons were added, with most of the other bottom and top end components coming from Fleece. The fuel system was another major addition Reynolds made, including S&S injectors, 14mm injection pumps, and a new SP3000 fuel pump that got mounted on the front.

Reynolds opted to only use a single turbo for his setup, however, the Garret GTX55 Gen4 is paired with a large amount of nitrous to compensate.

“As far as how much we spray, I’m not sure,” he says. “But, we run two 15-lb. bottles through a progressive controller. There’s seven jets plus a Nitrous Outlets intercooler plate, then we have four solenoids on it.”

Photo by Cheyenne Alexx

All in all, the truck makes around 1,800 horsepower and Reynolds intends to increase that number after some suspension issues are ironed out. Reynolds has raced it in ODSS events and ran it in Lights Out this year. The fastest it’s run to date is 5.51 at 136 mph in the eighth mile.

“It’s a pretty simple setup, but it works well for us.”

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].

You May Also Like

Billet 6.0L Powerstroke Engine

Leave it to Jared Alderson and the guys at Kill Devil Diesel to build a kickass Powerstroke engine! This competition-level, billet aluminum 6.0L will be going under the hood of KC Turbo’s truck for the upcoming race season. Check it out!

It’s always a treat to see the range of engines that can be built by a single machine shop. Some guys opt to revolve their builds around a particular engine platform or even within a particular horsepower range, and others tend to put out something different each and every time an order comes in the door. Jared Alderson and Kill Devil Diesel fall somewhere in the middle of those two.

Compound Turbo 6.7L Enforcer Engine

The popularity of D&J Precision Machine’s Enforcer series engine can’t be understated. We checked this one out at the 2022 PRI Show.

Coffman Starter 24-Valve 5.9L Cummins Engine

This 24-valve 5.9L Cummins is your average workhorse build for pulling trailers… until you learn about the Coffman-inspired starter James Crutcher built for this engine.

6.7L Powerstroke Engine

The 6.7L Powerstroke may have some some minor flaws, but they are easily remedied by the team over at Choate Engineering Performance.

12-Valve 6BT Cummins Engine

Eric Lucy and his 16-year-old son have been hard at work over the past two years building a 12-valve Cummins to drop into his F-250 King Ranch. Check it out!

Other Posts

Jason Sack’s Turbocharged 429 cid LSX Engine

Jason Sack had arguably one of the nicest Novas we saw during Sick Week 2023. The car’s beauty had some sort of gravitational pull as we walked passed it in the pits. Naturally, we gave in and stopped to have a chat with Jason Sack about his 1969 Nova and its turbocharged 429 cid LSX

Kill Devil Diesel’s 7.0L Billet Powerstroke Engine

The team at Kill Devil Diesel does some amazing work surrounding all light-duty diesel engines, but the Poplar Branch, NC-based shop specializes in Ford Powerstroke work. As such, they do a ton of trick stuff on 6.0L Powerstrokes, and we got a first glimpse at a billet 7.0L/6.0L Powerstroke build for Charlie Fish of KC

Intellectual Horsepower: Light & Medium Duty Diesel Replacement Parts

*Skip to the video at 1:37. Engine Builder Editor, Greg Jones, talks to Paul Kelly from Maxiforce and Bryan Menke from R&R Engine and Machine about “Light to Medium Duty Diesel Engine Parts.” From skid steers to back hoes and mini excavators, these machines are being used at a high rate and are often in

Twin-Turbo 427 cid LS Engine

Somewhere in the range of 1,500-1,700 horsepower, this LS-powered ’68 Chevelle made a new personal best pass for owner Tanner Stover at Sick Week this year. Check it out!