a call,” he says. “I’m not sure if Jason [Wehrli] believed that I was going to build up the truck as much as I wanted because it was still so new and it was running perfectly fine. But he always returned my calls right away and talked me through all my plans, so within a few months it was at his shop.” What they had planned for the truck was big, with the engine, transmission and chassis all receiving modifications. In fact, the LML engine itself (which was still running fine) was unceremoniously yanked out of the truck, signaling the start of the big build.
Since the LML blocks are already so strong from the factory, the block itself received very little work other than a girdle and main studs, which replaced the factory bolts. The crankshaft was also left stock, but the connecting rods were replaced with much stronger Carrillo versions and the pistons are Mahle oval-bowl designs. The engine also had a set of ARP head studs installed and the factory cylinder heads were ported, polished and fitted with performance valve springs. Once upgraded, the engine was reassembled by Wehrli Custom and stuck back in the truck. The focus now would be on making some serious power.
Compounds and Twins
Because the factory-sized injectors can only spray so much fuel before they just start making heat, one of the major steps in the build was adding a set of Exergy Engineering 80% over injectors fed by twin CP3 pumps modified by Wehrli. That way fueling wouldn’t be an issue, even as power approached 1,000 rear-wheel horsepower. The stocker/s475 compound turbo setup wasn’t going to cut it either, so two billet-wheel turbos from Engineered Diesel were secured, one 66mm S300 and the other an 84mm S400. Again, it was Wehrli who built the outrageous orange piping to funnel the charge through an AFE intercooler.
The Duramax engine in Daniel Dillon’s 2011 Chevy is quite a piece. Built by Wehrli Custom Fabrication, the powerplant puts down 942 hp to the wheels. It was assembled from the bottom up with a stud girdle, ARP main studs, Carrillo connecting rods and...
Special attention was paid to keeping the exhaust side from frying the firewall. The turbo piping from the small to large turbo snakes along the back of the engine and is heat-wrapped to reduce under-hood temps.
The custom compound turbo kit was also built by Wehrli Fabrication and features an Engineered Diesel S366 turbocharger. A billet wheel improves both reliability and flow.