From mechanical 7.3L to common-rail 6.7L to P-pumped 6.7L Power Stroke, Ferenc and Nathan Vegh are determined to get a blue oval out front in the dirt.
Since 2018, Ferenc and Nathan Vegh have been campaigning the only Power Stroke propelled Ford in the Pro Stock Diesel Truck pulling category. In that time, this father and son team’s battle-hardened ’16 F-350—coined Jumping Jack Flash thanks to their deep-rooted affinity for the Rolling Stones—has sported three very different V-8’s under the hood. Early on, the Vegh’s relied on a mechanically injected, P-pumped 7.3L to get the job done. Then came the switch to a 6.7L Power Stroke, where smaller displacement and electronically controlled common-rail injection better suited them in the air-limited Pro Stock class, in which only a single, 3.6-inch smooth bore turbo can be run.
But midway through the 2024 season, something crazy happened. After fighting recurring electrical and mechanical gremlins, the Vegh’s returned to mechanical injection. And no, they didn’t revert back to the 7.3L… This time the truck was fitted with the world’s first P-pumped 6.7L Power Stroke. By no means are Ferenc and Nathan done with common-rail injection (keep reading for the full scoop on that), but when we caught up with them at the 2024 Scheid Diesel Extravaganza they were enjoying what the mechanical 6.7L brought to the table. This is the inside story of the only P-pumped 6.7L Power Stroke ever built—and the only Ford-powered blue oval competing in the Pro Stock field.
If you look into the history of Jumping Jack Flash, you’ll find that Ferenc and Nathan Vegh have kept the truck Ford-powered since it was introduced—something that rarely happens in the sport of truck pulling, with most converting to Cummins power in short order if not right from the beginning. Since the beginning, their engines have been designed, built, and tested by Hypermax Engineering, a company with half a century of truck and tractor pulling success and innovation behind it. All of the one-off engine parts, assembly, fabrication, and most of the fuel system components on the Vegh’s engines have come from this storied, northern Illinois facility.With 40 hours of machine time wrapped up in each billet-aluminum valve cover alone, the covers—along with the heads—integrate four mechanical fuel injectors per bank. The heads themselves are un-ported, OEM reverse flow units cut to accept fire-rings, fitted with Hypermax Hi Rev valve springs, and anchored to the block by way of ARP studs. Below the heads and within a factory CGI 6.7L Power Stroke block that’s also been machined to accommodate fire-rings, an OEM-based crankshaft—secured via the 4-bolt mains with cross bolts arrangement and ARP main studs—slings a set of Wagler connecting rods. The forged rods are topped off with Mahle forged-steel pistons that’ve been treated to deep valve reliefs in order to complement a custom grind 6.7L camshaft. Compression checks in somewhere around 13.5:1.Nothing commands attention better than a monster-size P-pump, and the Jumping Jack Flash Ford sports this monstrosity in the valley. Produced completely in-house at Hypermax, the cast-aluminum body, eight-cylinder pump features 15mm plungers and barrels, a high-lift camshaft, an Ag governor, and custom-bent injection lines. The 15mm unit receives ample low-pressure fuel supply from a FASS system mounted near the driver side radiator core support. We’re told pump timing sits between a healthy 45 and 48 degrees.As we alluded to earlier, extensive machining was necessary for both the cylinder heads and the one-of-one valve covers to seamlessly integrate the mechanical injectors. The International-based, 7-inch long, pencil-type injectors are also products of Hypermax Engineering. They make use of triple-feed bodies to inject as much volume as possible during a relatively short injection window. Their spray angle has also been precisely matched to the fuel bowl present in the modified steel pistons beneath them.Due to the design of the 6.7L Power Stroke’s reverse flow heads, Hypermax positioned the turbo at the back of the engine, near the Lexan firewall. Class rules dictate that a single, 3.6-inch smooth bore (non-map groove) charger must be run in the Pro Stock Diesel Truck category, and this T6 unit came from the folks at Wimer Fuel Injection and Turbo. The 91mm turbo builds as much as 80 psi of boost during the course of a pull. The exhaust manifolds, up-pipes, and collector were built by Hypermax, not to mention all of the intercooler and intake piping.Water-to-air intercooling works wonders in truck and tractor pulling, and perhaps no one builds a nicer, more effective water-to-air unit than Sandridge Custom. It rides shotgun next to Nathan in the cab and, in conjunction with an ice box setup, EGT rarely crests 1,700 degrees F. And if EGT ever reaches 1,800 degrees, the water injection system is triggered, dropping exhaust temps back down to where the heavily fueled V-8 is at its happiest.Horsepower begins its journey toward the axles via a four-disc clutch and pressure plate from Molinari Racing Products, and the competition clutch does its thing inside a Custom Floaters bell housing. Next in line sits the common (and all but unbreakable), one-speed reverser transmission from Profab Machine. A Profab quick change transfer case (i.e. drop box, shown) routes power to the front and rear axles. Also notice the Proformance Pros sticker, which is present on the driver’s seat mount. Other than what’s under the driver, there is no floor present in the truck’s cab.In the fall of 2021, Ferenc and Nathan dropped the truck off at Norman Newswanger’s place, the owner and driver of the Cummins-powered “Chapter 11” OBS Ford that runs the Pro Stock circuit. While there, Jumping Jack Flash was treated to an updated hitch and a few weight-saving measures (including gutting the steel bed). The Meritor/Rockwell 20-145 rear axle you see here, which sports an Advanced Chassis aluminum center section and a spool, has proven rock-solid over the years. Up front, a Rockwell F106 fitted with a Detroit locker has no issue handling the rigors of truck pulling.Jumping Jack Flash rarely becomes unsettled during a hook, and this is part of the reason why. The truck’s four-link front suspension system keeps the front Rockwell planted in the dirt, and a pair of adjustable coilover shocks are present on each side of the axle. The coilovers offer plenty of pre-load adjustment capability, which essentially means the front suspension can be fine-tuned for any given track or track condition. As for steering, a complete hydraulic system from PSC Motorsports makes the cut-tire Ford extremely maneuverable in the pits. The Vegh’s family friend and longtime pulling enthusiast, Will Hardesty, was responsible for the truck’s initial chassis, suspension, and steering system work, as well as its overall upkeep.When you see it, you know there is more to the truck than just a name. Ferenc and Nathan are die-hard fans of the world’s greatest rock and roll band and this little bit of added flair ties in with everything else the Veghs do (which entails blasting The Stones’ greatest hits in the pits). Not unlike a lot of high-end pulling trucks, Jumping Jack Flash sits on 34×18.0-15-inch Nichols “Pulling Edge” cuts mounted to 15×18-inch aluminum Real Racing Wheels. Nathan tells us they run just 8 to 10 psi up front and 20 to 24 psi in the rear tires, depending on the track.From the Simpson Race Products’ TS-R driver seat, Nathan is bombarded with gauges that display everything from boost to fuel pressure and water temp to oil pressure. But during the heat of his 15-second, 300-foot battles with the sled he rarely pays attention to any of them. The driving duties alone are a full-time job with 1,700-plus horsepower on tap. The giant tach is one analog gauge Nathan does pay attention to, with the needle tapping 5,000 rpm leaving the line and carrying 4,600 to 4,850 rpm while heading down track.Few pullers can say they spent their high school and college years driving a Pro Stock diesel truck, but Nathan Vegh can. Thanks to his father’s addiction to the sport (which consisted of campaigning a 7.3L-powered Super Duty back in the early 2000s), Nathan has practically grown up around truck and tractor pulling. These days, even as Nathan finishes up his master’s degree at the University of Mississippi, it’s not uncommon for him to drive 500 miles each way to meet his dad at the track and strap into the driver’s seat. In the past, aforementioned family friend and the original builder of the truck, Will Hardesty has been the truck’s stand-in driver.The track is one of the biggest variables in truck pulling, but at most venues you’re guaranteed to hear the throaty, 5,000-rpm roar of the only 6.7L Power Stroke V-8 in the Pro Stock class, followed by watching Jumping Jack Flash build a very big head of steam. Before the sled operator drops the hammer, the truck typically builds 32 to 33 mph worth of ground speed. Plans for 2025 entail running the Pro Pulling League circuit and hitting a few Mid-South Pullers Association hooks, beginning with the “Showdown in the Swamp” on March 28-29.But there is even bigger news for Jumping Jack Flash in 2025. As we went to press, Ferenc and Nathan were preparing to give the common-rail 6.7L Power Stroke another go. Engine updates from Hypermax, quicker firing injectors from S&S Diesel Motorsport, and promising numbers on the dyno suggest that high-pressure common-rail provides the best path to the winner’s circle. “We’re tired of experimenting,” Ferenc tells us. “We want to win!” Equipped with some of the most advanced piezo injectors ever developed, three S&S-supplied high-pressure fuel pumps, and a MoTeC ECU with S&S firmware, the latest Hypermax engine might just have what it takes to push Jumping Jack Flash to the front of Pro Stock this season.
