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Diesel truck owners often show extreme loyalty to a particular brand. Decisions often get made based on whether a truck has a Duramax, a Cummins or a Powerstroke engine. We get it – everyone has their niche – and the engine building world is no different.
Many engine builders devote their full time and attention to one particular engine brand. Some love Duramax engines, while others (many others) like to utilize the Cummins platform when building a powerhouse racing or pulling machine. Whether that be through a hobby or full-fledged business, these focused builders often become experts in their respective platform.

Brian Jelich is a prime example of someone who’s stayed consistent with his interests for years and proved his expertise in the craft. For 18 years, Jelich has been tooling on the same 2000 model year F-350 that he bought when he was just 18 years old, slowly upgrading and improving the truck. As we often see in the industry, man becomes attached to machine.
“I don’t think I’ll ever sell this truck,” Brian Jelich says. “I’ve had it for half my life, so it’s definitely become extremely important to me.”

Jelich got serious with the truck’s performance a few years after purchasing it in 2004. He started making a name for himself in 2010 when he began running mid-10s in the 1/4 mile and most notably, was the first 7.3L Powerstroke to break 1,000 horsepower on a chassis dyno.
After more and more racing in the 5.90 index class and personal tuning, Jelich’s passion led him to start JeliBuilt Performance LLC in 2017. Despite being a small, two-man operation, JeliBuilt Performance offers several services to its customer base. Most notably, Jelich provides reliable and quality tunes for Powerstroke trucks using Power Hungry Performance Minotaur Software. In fact, Jelich personally tuned a Hydra Chip that the late Brian Gray of Gray’s Diesel Performance relied on to dial in his 1,700-plus horsepower Pro Mod which was the fastest 7.3L truck in the world.

All the while, Jelich has continued to enhance his F-350, and the uber-powerful 444 cid turbocharged 7.3L Powerstoke engine hiding underneath the hood. His truck currently holds its own record as the fastest 1/8th-mile 4×4 7.3L Powerstoke in the world.
What’s most interesting is that despite a different cam and heads installed on the engine in 2015, the 7.3L long block has essentially stayed the same since 2012 when Jelich first built the motor with a friend. The main caps are tied together by a main bearing girdle, which is secured with the crank by ARP main studs.

The camshaft is a Gearhead Automotive Performance Stage 2, which works flawlessly with the ported and fire-ringed Crutchfield Machine heads hidden by polished-aluminum Moroso valve covers. For connecting rods, the engine features a billet prototype Tymar set, and the cast-aluminum pistons from Mahle are de-lipped and decked.
To compete with other competitive race trucks, 7.3L users often have to find a solution to the many stock injection issues of the platform, including the injector pressure regulator going bad and slow injection rate.

On the fuel side, Jelich opted to install the largest injectors he could find from Unlimited Diesel Performance, a set of 455/400 hybrids. A Swamps Gen III high-pressure oil pump mounted over the stock Super Duty HPOP supports the injectors, which are capable of moving 455CCs of fuel through 400% over nozzles. The entire system circulates around an Aeromotive A1000 fuel pump that has a regulated return and a -6 AN fuel line.
At one point, Jelich sported a compound setup on his truck but has since ditched the dual turbos for a big single turbo to feed the 7.3L – a BorgWarner S480 from KC Turbos currently sits atop the engine and packs 70-psi of boost into the On3 Performance intercooler. The exhaust manifolds were fabricated by Paul’s Custom Fabrication and Machine, and they help drive the 80/96/1.32 charger.

All in all, the truck belts out around 1,500 horsepower with Jelich anticipating an increase in power happening soon.
“I think it’s probably got another 100 or so horsepower in there pretty easily,” he says. “I just need more time on the track to test things out.”

It’s pretty safe to say that more time on the track will bring steady improvements for Jelich this year, as it has in the past. In fall 2021, Jelich smashed through his previous record of 5.76-seconds at 121 mph in the 1/8th-mile. Currently, his record pass is 5.46-seconds at 127 mph.
“My goal this year is to run low fives — I’m thinking 5.10s or 5.20s. If I can get another .10on the 60 foot and another 100 or 200 horsepower, we’ll get there.”
Here’s to hoping he does!

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].