1,900-Plus HP LLY Duramax Engine - Engine Builder Magazine

1,900-Plus HP LLY Duramax Engine

With aspirations of a 2,000-horsepower 6.6L LLY Duramax engine, Morey Logue of Interstate Diesel Performance is just on the verge of hitting his goal. Check out what's helping him get there!

Diesel of the Week is presented by

After trial and error and a lot of lessons along the way, Morey Logue made it his goal to hit 2,000 horsepower with his 6.6L LLY Duramax engine, a feat that only a few have conquered. He hasn’t made it quite yet, but he’s about as close as he could be.

Logue moved out to Layton, Utah, just outside of Salt Lake City, two years ago, and began working at Interstate Diesel Performance as a technician. It’s a one-stop shop that does everything from oil changes to performance overhauls. However, his current stint at Interstate isn’t where his project began.

“Way back in like 2010, a buddy of mine had a 12-valve Cummins, and I think my interest started around then as it did for a lot of people when they found out you could pull the fuel plate out of it to give it some more horsepower,” Logue says. “That was pretty cool, and we did a lot of tinkering on it. A year later, I bought my first Duramax.”

Over the next couple years, Logue bought and worked on a Cummins before focusing on other things. However, he was drawn back into the diesel world rather quickly.

“A buddy of mine had the Duramax I have now sitting in his barn for maybe two years or so,” he says. “I knew the thing was supposed to be pretty fast, so we discussed it for a while, then I finally made the deal.”

Logue started working on a race build straight away, and the initial goal was to make it into the Diesel Power Challenge. In 2020, he was in the running for the event, with his first setup making around 1,000 horsepower on fuel and 1,100 on nitrous.

Covid put a halt on the event permanently, but at the time, it was probably in the best interest for Logue to pass up competing anyway. He had guessed that the engine was on its last leg, and sure enough, a tear down shortly after confirmed his suspicions. Since then, he’s dropped another Duramax under the hood and started a journey to improve the performance of his LML as much as possible.

“It’s been a learning curve for sure,” he says. “We went through a lot of pushrod failures and had to switch brands, had some issues with the alternate firing cam and getting that to breathe right, and on one run it blew the V-band clip off the atmosphere charger and that caused a ton of issues.”

Trial and tribulation often bring the best results though, and Logue’s current setup boasts an incredible 1,925 horsepower. Just short of his ultimate goal, the truck is rocking some intense upgrades. The 6.6L Duramax is an LML block with LLY electronics in the truck.

The engine features Manton pushrods, Wagler valve springs, Wagler ported and polished heads, Ross forged pistons, and a Callies Ultra billet crank. Also from Wagler are the billet main caps and their Duramax street girdle. The girdle and everything else on the engine uses ARP hardware.

The turbo system changed a few times over the course of the build, with Logue eventually settling on a High-Tech turbo 83/87 in the valley and a Garrett GT5541R on the atmosphere. All of the fabrication work for the setup was done in-house by Interstate Diesel.

“The turbos work great and spool perfectly,” Logue says. “I discussed what more we could do with some people, and we decided that a second CP3 would work well, so now there are two injection pumps from Industrial Injection – a 12mm and a 10mm.”

A FASS 290 lift pump provides the engine with enough fuel and protects the injection system. Logue runs four solenoids from Nitrous Express and Turbo Smart wastegates, all with 35-lb. spring zones. A Mishimoto intercooler rounds out the engine build.

“I want to get that 2,000 hp at least once,” Logue says. “Maybe if I had held my tongue just right in the cab, I would’ve hit it already. But it’s coming. After that, I’ll probably downsize it a bit and get back down to around 1,300 horsepower for racing.”

Expect to see Logue and the team at UCC in a few weeks, where he’ll be putting his build to the ultimate test!

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

Compound Turbo 6.7L Cummins Engine

Many of the guys at the top of the diesel sled-pulling totem pole often use the 6.7L Cummins for their builds, both for its reliability and efficient power making potential. Michael Brown just finished up work on this Cummins that he’ll be using this year at events like King of the Street. Check it out!

It’s no doubt that sled-pulling requires a fairly powerful engine under the hood of any competition truck – propelling a ~55,000-lb. weight transfer sled across a dirt-packed track is no easy task. For that reason, competitors take a lot of time fine-tuning their truck and engine setups to produce the most effective and efficient combination.

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!

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.

Other Posts

Choate Engineering Performance’s 6.7L Powerstroke Engine

Choate Engineering Performance, located in Bolivar, TN, does a ton of diesel engine remanufacturing and custom engine building. We were recently visiting the shop and got the run down of Choate’s 6.7L Powerstroke build. It’s our Diesel of the Week! Related Articles – Jason Sack’s Turbocharged 429 cid LSX Engine – Kill Devil Diesel’s 7.0L

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

Nitrous Update

The use of nitrous oxide in diesel engines is not a new concept. In fact, it has been used in drag racing for decades. However, it is only in recent years that it has gained widespread popularity in the worlds of diesel truck pulling and drag racing. Now, it seems as if almost everyone in the competitive scene is using it.