Justin Zeigler's UCC Record-Setting 6.7L Cummins Engine - Engine Builder Magazine
Connect with us
Close Sidebar Panel Open Sidebar Panel
6.7L Cummins Engine

Diesel of the Week

Justin Zeigler’s UCC Record-Setting 6.7L Cummins Engine

Diesel of the Week is presented by

Click Here to Read More

Well, he’s done it again. For the second year in a row, Justin Zeigler of Zeigler Diesel Performance has won the Ultimate Callout Challenge. He’s been a big name in the diesel performance scene for some time now, but this may just be his crowning achievement. That is, unless he tops himself in the future.

Over the course of the three-day UCC event, 15 competitors duked it out across different events: drag racing, the chassis dyno, and sled pulling. The repeat win from Zeigler didn’t come without some fierce competition throughout the weekend, with Derek Rose finishing only 77 points shy in second place, and Tony Burkhard and Chris Patterson trailing closely in 3rd and 4th, respectively.

Day 1 featured excellent drag racing, with three competitors – including Justin Zeigler – all making 4-second passes. Day 2 was the highlight of this year’s event though, and will undoubtably be the talking point that gets thrown around until UCC 2023. Since the event started in 2016, competitors have been chomping at the bit to build huge horsepower, with 3,000-horsepower being the ultimate goal. Obviously, this feat has been done in the gas world and more recently in the diesel world outside of the UCC competition. However, the chassis dyno requires traction, especially when talking about 3,000 hp.

This wasn’t an issue for Zeigler though, who came out on top with shocking results. Zeigler dyno’d his truck last in line, and at that time, 2,621.1 horsepower and 3,677.3-lb./ft. of torque were the numbers to beat. While it was expected that his Cummins would produce big numbers, no one expected what would happen next.

Not only did Zeigler hit that 3,000-horsepower mark, he shot passed it in a triumphant dyno performance that resulted in a whopping 3,336 horsepower and 3,642.20-lb./ft. of torque! Surpassing second place by over 700 horsepower and setting a monumental new event record is more than you can ask, but even more impressive is that his dyno performance came off the heels of him making a 4.99-second pass the day before. This was the first time Zeigler made a 4-second pass, and it was in his Super Stock 2nd-Gen Ram, which had previously not been out on the track since Justin bought the truck.

Needless to say, Zeigler didn’t show out this hard by chance. Under the hood of his truck is a powerhouse compound turbo 6.7L Cummins engine. The engine consists of a D&J Precision Machine Enforcer series deck-plated long block, which features an OEM, cast-iron block machined to accept cylinder sleeves and a 1-inch deck plate, along with a cylinder head cut to accommodate fire-rings. The long block also includes FSR pistons with Total Seal piston rings, HD deck plate, 7/16ths pushrods, ARP head studs torqued to 175ft./lbs., ARP 9/16th main studs, and several other D&J manufactured components.

“This is the same engine we ran last year,” Zeigler says. “We actually converted it to run dry, so the block isn’t filtering like that and we pulled all the soft plugs out. We got Exergy 400% injectors in it, two of their 14mm pumps, their billet rail, and a full Bosch handle and ECM from them.”

For the air setup, Zeigler implemented compound turbos, with a 5.3″ Wimer Fuel Injection low-pressure unit out front and an 88mm Garrett GT55 on the manifold. The massive atmosphere turbo from Wimer packs a 135mm compressor wheel and utilizes a T6 turbine inlet flange, routing the exhaust out a 6-inch hood stack.

Inside the cockpit, the team at Zeigler Diesel Performance has data on everything.

“Lavon Miller of Firepunk Diesel is doing Lavon on the laptop,” Zeigler told us. “You’re just guessing without all that data, and that’s the great part about that Bosche ECM. On that 4.99 pass, we used 6 lbs. of nitrous in 1.19 seconds.”

Zeigler’s record-setting truck also features a Rossler Turbo400 transmission, a Neal Chance racing converter, and an SCS Gearbox Inc. transfer case.

It’s insane to think about how far diesel performance has evolved over the past decade. Diesel engines are getting stronger by the minute, and next year, it’s going to be interesting to see competitors try and get close to that 3,336-horsepower mark. UCC dyno day 2023 might be highlighted by pulls close to 3,500 horsepower, or even 4,000. We can’t wait to see the inventive ways these guys go about building power, and we’re sure will see Zeigler Diesel Performance on the list of top performers. See the dyno pull below.


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

Engine Builder Magazine