1,300rwhp ‘Fummins or Z06 Corvette: Which One Would You Drive?
Thanks to the tremendous untapped potential trapped inside the modern diesel engine, namely the Cummins, an insane amount of horsepower (and gobs of torque) can be unlocked. Not only has this fueled the “Cummins swap” craze, but it’s also made it possible to make some pretty wild comparisons. For instance, a four-wheel drive, Cummins-powered, compound turbo’d ’99 F-250 making a dyno-proven 1,368 hp at the wheels vs. a moderately modded ‘07 Z06 Corvette that runs high 10’s. Despite their obvious differences, the comparison isn’t as far-fetched as it might seem…
In a conventional drag race, with adequate traction the lightened Super Duty could potentially wallop the ‘Vette thanks to its triple-digit boost, four-digit horsepower and (of course) its use of four-wheel drive. But from a roll, a blast beyond 130-mph or handling at virtually any speed, Chevrolet’s iconic sports car is the obvious and hands-down winner. So why even make the comparison? Because when enough horsepower is involved, two completely different worlds can be made to collide. And when raw power meets factory refinement, you get this type of forced altercation.
It’s work truck-turned race truck vs. sports car, Ford vs. Chevy and diesel vs. gas. Which would you rather drive?
Fummins vs. Corvette (6,000 Pounds vs. 3,100 Pounds)
It’s the Ford vs. Chevrolet comparison you could’ve only imagined in your dreams, but trust us this odd couple is worth comparing—and both are legitimately fast. The truck, a severely-lightened ’99 F-250 Super Duty owned by Mike Bean, has been 6.40 at 112 mph in the eighth-mile (on an older, less powerful setup than the current one, no less). The car is an ’07 Z06 Corvette that’s been treated to a few goodies and run high 10’s in the quarter. It’s owned by Mike’s son, Tyler Bean. We can only imagine what the conversations are like sitting around their Thanksgiving table... Check out the DNA of both of these wild rides below.
'07 Chevy Z06 Corvette
Hard-Part LS7 Upgrades
In bone-stock trim, the 7.0L LS7 in the Z06 cranked out 505 hp at the flywheel, but this baby has been anything but untouched since it left the factory. The heads were milled for higher compression, treated to a full radius valve job and fitted with new bronze valve guides, Manley swirl polished stainless steel exhaust valves, Titanium intake valves and Brian Tooley Racing dual valve springs with titanium retainers. A BTR stage IV cam, new lifters, Comp Cams’ rocker arm trunnion upgrade kit, Katech C5-R timing chain, fresh GM timing gear and ARP fasteners also made their way into the LS7.
Lots of Air
The naturally aspirated LS7 sees plenty of additional airflow thanks to an MSD Atomic AirForce intake manifold. The manifold features bell-mouthed runners that’ve been treated to porting for optimum airflow and its design allows for a 102mm drive by wire throttle body from Nick Williams Performance to be run. Gains of up to 36hp have been realized with the unported version of the Atomic AirForce intake manifold alone. A Vararam Industries’ VR-SC1R ram air system tops off the airflow mods.
Beyond the Badge
Without a doubt, the C6-Z06 vettes are “affordable fast.” In terms of performance, the LS7 makes them miles ahead of what the base model cars brought to the table and clean, low-mile Z’s can be had for $30 to $35K. As for this version, the mods didn’t end with intake and valvetrain upgrades. A set of OBX 1-7/8” stainless steel long tube headers and 3-inch MagnaFlow exhaust help the 427ci engine exhale, while Matt Sanford of Skye Performance handled the ECM tuning, using HP Tuners software. As for the transmission, the factory T-56 six-speed manual has been flawless, along with the dual disc performance clutch from South Bend that sends power its way.
To keep ahold of the track or street, a set of P345/30R19 Nitto NT05R Drag Radials got the call. A DOT-compliant competition tire, the NT05R’s unique race compound and wide contact patch are specifically engineered for maximum traction so you can get off the starting line as quickly as possible. The 13.5-inch wide drag radials were aboard the Z06 when it made its 10-second passes, as well as when Tyler ran the car up to 170-mph (we know, it’ll go faster than that).
Back when the Z06 had a slipping stock clutch it still managed a 10.97 at 129 mph through the local quarter-mile. Thanks to the new South Bend clutch, Tyler believes the car can manage mid 10’s on motor. After that, he plans to turn on the bottle and see what his direct port nitrous system from Nitrous Outlet can do.
'99 Ford F-250 Cummins Swapped
Common-Rail Cummins Swap
Once you realize Mike Bean is related to Ryan Bean of Bean’s Diesel Performance, his Cummins conversion begins to make sense. Once upon a time, Bean’s specialized in Cummins swaps (and now manufacturers the kinds of parts that simplify the conversion process) and pretty much all of them left the shop making stupid power. Built to survive 1,500-plus horsepower and more than 2,000 lb-ft of torque, Mike’s engine utilizes a sleeved 6.7L Cummins block, a Monster Pump Mike girdle with 14mm ARP main studs, Carrillo forged-steel rods, Mahle Monotherm (forged-steel) pistons, a cam from F1 Diesel and a 24-valve head that received porting, polishing and other loving at Enterprise Engine Performance, as well as 14mm ARP head studs. And (in case you’re wondering) yes, the For Sale sign means the truck is currently up for grabs. Interested, serious potential buyers are encouraged to reach out to Bean Machine and ask for Michael Guthrie.
The 76mm Turbo is the Small One…
A massive compound turbo arrangement is brought to life thanks to this BorgWarner S400-based charger serving as the high-pressure unit. The T4 turbo features a 76mm compressor wheel and bolts to an ATS exhaust manifold. To keep it from overspeeding, a 45mm external wastegate from Synapse Engineering ensures the S476 is never exposed to too much drive pressure. In a lot of compound turbo arrangements used on diesels, a turbo this size usually serves as the atmospheric unit (i.e. the bigger charger of the two).
91mm Atmo Charger
Well-concealed near the firewall and underneath the S476 sits the low-pressure (atmosphere) charger. Even bigger, it’s an S500 series BorgWarner with a 91mm compressor wheel. At full song, the S476 over S591 combo crams 120 psi of boost through the Mishimoto air-to-air intercooler, a Bean Machine side-draft intake and ultimately the worked over head.
Bringing 1,200-plus horsepower worth of fuel into the equation, a set of injectors from F1 Diesel were equipped with nozzles that measure 400-percent larger than stock. To keep the fuel rail full, rail pressure high and the big injectors happy, two 12mm stroker CP3’s from Fleece Performance Engineering are employed. One pump sits in the factory location while the top CP3 is cog-belt driven. The electronically controlled Cummins’ ECM is calibrated using EFI Live software.
Strapped to the chassis dyno at Bean’s Diesel Performance (a load-cell Dynocom), Mike’s Fummins cleared 1,015 hp on fuel. Then with two stages of nitrous in the mix and the aforementioned 120-psi of boost achieved, 1,368rwhp was recorded. Don’t mind the torque curve, the tach signal was not reading accurately during these pulls. Other visits to the dyno subjected the tread out back to more than 2,300 lb-ft of twist!
It’s Lighter Than It Looks
As for the rest of the truck, it sports the factory transfer case, an untouched Dana 60 up front and a Dana 80 out of a Ford dually (cut down by Hudlow Axle and graced with a Lincoln locker). It’s not a problem anymore, but the truck ate 14 different transmissions before the current parts recipe inside the 4R100 was able to stand up to the Cummins’ power. The full-billet four-speed makes use of a stock stall speed, triple-disc torque converter from Precision Industries. Surprisingly, the truck doesn’t possess the typical, 7,500-pound curb weight of an early Super Duty. In fact, Mike has gone to great lengths to strip as much weight as possible off of the ¾-ton over the years, which included ditching the leaf springs for coil overs and even building the hulking front bumper out of 3/16-inch aluminum to help shave weight. All told, Mike’s Fummins tips the scales at less than 6,000 pounds.
Interested in more Cummins swaps? Check out this 5.9L-powered ’76 High-Boy.