The path less traveled is either a glorious path or one of extreme trials and tribulations. No matter the outcome, the path less traveled will always be one filled with obstacles that no one has ever encountered. While there are hundreds of people taking the path less traveled, only a few choose the right one and have the endurance to finish strong at the other end. One such person is Wesley Kusilek of River Falls, Wisconsin, with his Cummins Killer II.

In December 2012, Kusilek decided he wanted to build a pulling truck. “I went to the junkyard and got a cab and chassis. We stripped it down and started bracing and modifying it. It took three months until we made it to an indoor pull. Since then, we have made only a few changes. The truck has proven to be a top runner in the 3.0 class,” said Kusilek.

The full-blown pulling truck started life as a 2013 2500 GMC Sierra Denali. Once everything was stripped down, the frame was braced and painted red. In the back, a custom Rockwell SQHD rearend was solidly mounted to the frame. Up front, Kusilek kept the factory front torsion suspension, but upgraded to a custom independent F106 Rockwell front axle built by Proformance Pros.

Both axles under Cummins Killer feature a 6.14 gear ratio and use Proformance Pros axles to turn the 16-inch Real Racing Wheels. The front wheels are wrapped by 35-inch Nitto mud grapplers. Out back, Kusilek opted to run dual Goodyear Wrangler Duratrac LT315/75R16s. With the sled responsible for stopping the truck on the track, there isn’t a big need for brakes on a pulling truck. Kusilek decided to remove the rear brakes and upfront, he opted to use a set of Proformance Pros brakes that are controlled with one of their master cylinders.

Once the rolling chassis was completed, the powertrain was next. The engine was sent to Wagler Competition Products for all of the machining. Ross Racing Pistons are connected to R&R Racing Products connecting rods. The rods are attached to a custom Winberg crankshaft. Between the oversized pistons and the longer stroke from the crank, Wagler was able to bump the displacement up to 7.4 liters.

To finish off the short block, a custom LSM camshaft was installed along with a Raceline external oil pump and custom oil pan. Certainly, the bottom end is special, but the top end is where the magic happens. To start off, the engine features a deck plate that ties the custom front and rear covers along with the engine block altogether. The cylinder heads are Wagler Competition Extreme series heads. These heads are custom designed by Wagler and CNC to ensure maximum flow. The heads are held down with ARP studs.

On top, a Wagler Competition custom air-to-water intercooled intake manifold ensures the shortest possible path between the turbocharger and the pistons. This minimizes response time and maximizes flow.

In regards to flow, the air for this beast of an engine is supplied by a Precision Turbo 3×4 with a 1.12 A/R turbine housing. The exhaust is directed from the heads through the custom exhaust manifolds fabricated by ProFab Performance. At wide open, the system produces about 60 psi.

The 3.0 class is an extremely competitive class with really big horsepower. In order for an electronically controlled Duramax to be competitive against the big Sigma pumps, Kusilek looked far and wide to find a set of injectors that could support the horsepower desired, but still be tuned electronically. Finally, deciding on a set of injectors out of a Case IH engine. These were then sent out to S&S Diesel Motorsports to be modified to flow an additional 400cc.

Injectors this large require a huge amount of high-pressure fuel and a single CP3 wouldn’t support them. In fact, two CP3s wouldn’t support them. Kusilek custom-designed a gearbox to run three S&S Diesel Motorsports CP3 pumps that have 10mm plungers. The three CP3s all feed a main fuel rail mounted on top of the gearbox. Then, the main fuel rail has two feeds, one for each cylinder head. The individual fuel rails are mounted under the valve covers.

This unique setup required a unique and powerful tuning solution. Kusilek turned to the guys at Bosch Motorsports for help. They ended up using one of Bosch’s stand-alone ECUs with custom tuning from Andrew Stauffer of Bosch Motorsports.

This setup is making about 1,700 horsepower at 4,000 rpm and 2,500 flb-ftof torque at 3,600 rpm. With this much power, putting it to the ground can be challenging. To ensure that Cummins Killer II is reliable, Kusilek turned to the guys at SCS Gearbox for a drop box. The drop box has two gear ratios, 1.64:1 and 1:1. The drop box is mounted on a Probell Racing Products bellhousing. A Molinari Racing Products (MRP) pressure plate and clutch assembly transfer the power back.

Another unique and interesting feature of the truck is the tilt cab setup. When we met up with them to shoot the truck, they said it took about a week to figure out how to do it, and it worked first try (a real tribute to their mechanical abilities.) The cab has a hinge located at the back of the cab. As the cab is moved up, there is a rod that pushes the bed back. The bed is mounted on a set of guides much like a drawer. The steering is hydraulic, so there are no steering shafts to disconnect. The hydraulics run to the back of the cab where the hinge is, then to the weight box where the pump is located.

As one might expect, the cab is all business. The factory interior has been completely gutted. A race seat and harnesses were installed. Then a hand throttle was fabricated right next to the stick shift for the drop box. The dash is extremely basic and clean. There is a fuse box on the side, a brake lock switch in the dash, and a Bosch DDU7 display mounted on top to let the driver know what is going on under the hood.

This is Kusilek’s third pulling truck and it shows that Kusilek has learned a lot of lessons along the way. Cummins Killer II is put together with some of the best parts in the industry and works extremely well. In 2014 (when we caught up to him) he was in first place in the Lucus Oil Pro Pulling League point series at Scheid’s Diesel Extravaganza but had a few oil pump issues.

Cummins Killer II finished second in points. “I cannot say thank you enough to all of my family and friends who have helped along the way. I have, also, been fortunate to have great sponsors like Precision Turbo, Wagler Competition Products, S&S Diesel Motorsports, Proformance Pros, and Bosch Motorsports,” said Wesley Kusilek.