Dyno, diesel swaps, and the cleanest trucks in the Midwest. Once again, WCFab proves why its biennial event is one of the best in the industry.
Build a name for offering high-quality, problem-solving parts. Accumulate thousands of customers while you’re at it. Then expand, construct a state-of-the-art shop, and invite the masses over for a party. In a nutshell, that’s what Wehrli Custom Fabrication has done. Every other year, the WCFab Open House attracts hundreds (if not thousands) of gearheads to DeKalb, Illinois for a fun-filled day of horsepower, show trucks (plus Jeeps and Broncos), parts and people representing some of the biggest names in the diesel industry, raffles, a live auction, and a percentage of the proceeds going to the Wehrli Custom Fabrication Scholarship Fund. The free admission event even offers pedal pulls and bounce houses for the kids.
Once again, the biennial celebration centered around the action taking place in the S&S-presented dyno competition, with 32 truck owners hitting the rollers for bragging rights, trophies, and cold, hard cash. At the top of the heap were UCC competitors Michael Brown and Cody Hawk. It was Cummins vs. Duramax—and both of them were gunning for the $4,000 payout in the Unlimited class. Hub City Dirt Drags regular and 5.90 Index racer, Christian Wichman, also made the call, as did a host of other entrants with four-digit horsepower potential. A short distance from the dyno, there were impeccably clean GM’s, Rams, and Fords to gawk at, along with several one-of-a-kind diesel swaps and even a few sleepers.
Only the Hawk Performance Diesel Duramax can blow apart its intake manifold and still win the dyno day… Cody Hawk, dyno pilot Morey Logue, and the rest of the team from Oxford, Michigan showed up at the WCFab Open House with 3,000 hp on their minds. With the UCC-tested ’02 regular cab Silverado already having cleared 3,140 hp on the Blessed Performance dyno in 2025, Cody and crew were looking to crack the 3K mark on the Northwest Dyno Series SuperFlow. After all, with the DHD-built LB7 packing dual Exergy Alpha 550’s, sizeable DDP injectors, and big compounds, Exergy’s System Application Engineer, Jeff Hale, tells us 2,000 hp is well within reach before nitrous even enters the chat.Unfortunately, the guys from Hawk Performance Diesel had to settle for a 2,347hp effort on the rollers. Not the 3,000hp number they were hoping for but still enough for First Place, the $4,000 payout, and bragging rights. On the truck’s second hit—and 500 rpm below where the engine makes peak power (at 5,500 rpm)—the welds on the passenger side intake manifold blew apart. Perhaps foreshadowing what was to come, on the morning of the event Cody Hawk asked Jason Wehrli if he was ready for his billet individual runner intakes to be “stress tested.” Jason responded by saying they’d pull the truck straight into the shop and he’d build new, stronger versions if they failed. Rumor has it these billet intake manifolds saw more than 200-psi of boost on the 2,347hp pull…Thanks to being a regular UCC competitor, Michael Brown is no stranger to the Northwest Dyno Series SuperFlow, and he too had 3,000 hp plans at WC Fab’s Open House. After making a fuel-only, 1,473hp pass first thing in the morning to test the functionality of the nitrous system, Michael was ready to make his big hit at 1 pm with a big crowd on hand. Unfortunately, a boost leak limited his efforts to 1,778 hp on the dyno, earning him Second Place on the day. If that issue doesn’t come up, Michael’s third-gen—which packs a D&J Enforcer series Cummins, Exergy pumps, Flux injectors, and 125mm G57 over S484 Taterbuilt compounds—north of 2,600 hp is easily on the table, just as it was when the truck made 2,698 hp at Firepunk’s place.There is a certain fearlessness when you’re playing the horsepower game with a budget-built engine as opposed to a $100,000 billet one. Such is the case for Christian Wichman of WB Motorsports & Diesel Repair. His non-deckplate Cummins is about as battle-hardened as they come, with more than 250 max effort dyno pulls and drag strip passes under its belt. Wagler Street Fighter rods and mild head work are about the only exotic components this common-rail has been treated to. The block, crank, and cam are all factory pieces, and even the pistons are cast-aluminum—yet it keeps on ticking. Flux 400-percent over injectors, a single 14mm Dan’s Diesel Performance CP3, and an AirDog system sum up the fuel side, while an AirTec Innovations S485 produces 90-plus psi of boost. WP Developments, Density Speed and Performance, and Westra Transmission & Fab also have a helping hand in the build. Christian’s second-gen laid down 1,769 hp on the rollers.Less than a week away from the Hub City Dirt Drags’ Diesel Truck Challenge, where he and his ’09 Ram would once again be strapped to the Northwest Dyno Series SuperFlow, Adam Matuszek made a big hit on the rollers. His 1,557 hp was tops in the Large Single turbo class, and along with bragging rights he took home a stack of cash and a trophy. It’s a performance that bested Freedom Racing Engines’ Nic Keck and his ultra-clean, S480 equipped ’06 5.9L, which laid down a highly respectable 1,318 hp.Cody Carlson also knew he’d be facing the same SuperFlow at the upcoming Hub City Dirt Drags’ Diesel Truck Challenge, so he brought his ’07 Dodge to WCFab’s Open House for a little dyno prep. The purpose-built quad cab out of East Troy, Wisconsin cleared a solid 1,247-rwhp on the rollers, which was good enough to take Third Place in the Large Single turbo class. Josh Widmayer, James Winchel, and Steve Jones would also turn in solid performances in the same category.We love a truck with a good story, and Daniel Ivaska’s ’06 Dodge checks all the boxes (plenty of horsepower, quick timeslips, immaculate condition, and sentimental value). Since stealing the ¾-ton Mega Cab from Texas 14 years ago, he’s gradually transformed it into a streetable monster. Despite tipping the scales at 7,900 pounds on race day, he’s still managed to get the 5.9L Cummins to cover the quarter-mile in 11.2 seconds at 121 mph. And even with a soft launch on that pass, the truck’s trap speed backs up the numbers it made on the dyno (1,052 hp and 1,670 lb-ft).The horsepower recipe for Daniel’s ’06 5.9L is simple yet effective. It starts with hard part durability and performance upgrades like Hamilton’s 188/220 cam, heavy-duty pushrods, tappets, and 103-lb valve springs, then gets serious in the fuel department with a Sportsman CP3 and 60-percent over injectors from Dan’s Diesel Performance. The truck’s billet shaft 48RE, weld-on traction bars, and S369 SX-E also came from Dan’s, while ARP 2000 head studs hold down the fort, an ICT Billet intake plenum and On3 Performance intercooler drop temps and feed boosted air into the engine, and two Nitrous Express kits add 200-230 extra ponies. Side note: God bless FASS Fabrication. There was a time when underhood mirrors like this cost a small fortune, and as such were rarely encountered on show trucks. Now, you can pick one up for $300.Sleeper alert! This is no bone-stock fifth-gen. Even though it looks tame (thanks in large part to the factory wheels), James Winchel’s ’19 Ram 2500 is an under-the-radar monster. What you can’t see from the outside is the truck’s added fueling, the S400 hanging from the manifold, or the fact that it’s been 48RE-swapped. An absolute sleeper, James’ late-model 6.7L Cummins runs 11.60s in the quarter-mile. That’s the element of surprise that makes driving a truck like this so fun. It can tow 20,000 pounds up and down the highway—and then hunt down pony cars in the very next breath.Remember the ultra-clean, 24-valve second-gen Wehrli acquired a couple years ago? Well, it’s got compounds on it already… In the beginning, WCFab used its 2000 model year Ram 2500 to develop a high-flow, 3.5-inch intake horn and intercooler piping kit for the VP44-equipped 5.9L, as well as the corresponding 3.5-inch diameter hot-side intercooler pipe and even an upper coolant pipe kit. How long before we see an S300/S400 compound turbo kit available on WCFab.com? With many enthusiasts dumping big money into older, pre-emissions era diesels these days, it’s no wonder there is still a market for the ’98.5-’02 trucks.A stock-appearing K3500 doesn’t usually stop us dead in our tracks, but we found this Duramax swap way too flawless to overlook. If GM had had the LB7 available for the GMT400 platform in 1993, it would’ve looked like this nestled into its 1-ton trucks. Owned by Josh Scott of Stanford, Illinois, the ’93 K3500 was treated to a used Duramax and a 4L80E automatic. The swap cost Josh roughly $10,000 to complete and he even had the Duramax and 4L80E conversion added to the original Monroney sticker, which he’d placed on the truck’s dash.A streetable show truck rocking a hood stack? We’ll allow it! Big single turbo Duramax’s never get old, and Martin Shelliam’s ’03 Chevrolet Silverado 2500 HD is about as pristine as 23-year-old trucks get. An S400 in the valley, a host of WCFab parts, and the perfect shade of purple powdercoating says Martin is just as interested in looks as he is in horsepower. You may have even spotted Martin’s ’03 Silverado shredding tires at the Raise Hell Roll Coal Truck Fest in Wisconsin Dells, Wisconsin.Anyone remember this gem? It’s the “ApacheMax” project Calibrated Power (now under the Wehrli Custom Fabrication umbrella) pieced together over a decade ago. A 1958 Chevrolet Apache body sits on a shortened 2003 Chevy Silverado 2500 HD 4×4 chassis and conceals an LB7 under the hood. The O.G. Duramax was built to live at 850 hp, sports a 14mm CP3 and 150-percent over injectors from Exergy Performance, a Stealth 67G2 turbo, and is backed by one of Calibrated’s DT1000 Allison transmissions. Fun Fact: before the 1,000hp-rated automatic was in place, the truck was equipped with a ZF-6.
