American Revolution: A Fox Body Mustang With a Chevy V8

Meet Doug

Douglas Schenck was a lifelong Ford man, but a stint in the Army took him to Germany and broadened his horizons a bit. “I met a wonderful fella who got me into racing motorcycles,” Doug says of his then-squad leader, Steve Broadstreet. “We’d spend our 16 Deutschmark to go run the Nürburgring.”

Doug became an aircraft mechanic, and he continued to absorb European gearhead culture throughout his service. He still hopped right back in his Mustang LX and Ford F-150 when he returned to the U.S., but the track experience on the Nordschleife left him pining for something with a bit more agility.

Meanwhile, Ford’s then-new SVT division was looking to demonstrate its ability to improve the breed, and its first salvo was the 1993 Ford Mustang SVT Cobra. It featured a worked-over 5.0-liter V8, Tokico dampers, bigger brakes and other upgrade. This was the final year for the Fox-body Mustang, and Ford only built 4993 examples of the SVT Cobra. The car’s 235 horsepower launched it from zero to 60 in just under 6 seconds, and it reached 98 mph as it shot down the quarter-mile in 14.5 seconds. Those figures are tame by today’s standards, but they were solid for the early 1990s.

Doug was driving by a dealership one day when he saw a black, late-model 1993 Mustang on the lot. It was an SVT Cobra. He made the snap decision to upgrade, passing his LX to his then-wife. Doug spent a year as a very satisfied customer, adding a Flowmaster exhaust to his new pride and joy.

But then an inattentive driver smashed into the SVT–and cracked open a new world of possibilities. “I figured it’s never going to be original anymore,” explains Doug. “That’s when I made the decision to start modifying it.”

Ford Faithful

Untethered from his desire to keep the SVT Cobra fairly stock, Doug snapped up some popular Mustang magazines from the era. But the pages of Muscle Mustangs & Fast Fords and 5.0 Mustang still left him wanting. “You see everybody with these Fox bodies was doing drag racing,” Doug says. “I came of age in Europe.”

Doug’s cousin encouraged him to try track days. While that venue gave Doug a great place to play, he had to rely on trial and error as he strove to get his Mustang around the track more quickly.

“I went through two different K-members that were drag-oriented things,” he recalls. “I kinda learned from experience. The car had a pretty decent powerplant in it stock. In Europe, power isn’t everything, so I focused on the handling and braking, where the Cobra had a bit of a leg up on the others. I got introduced to Maximum Motorsports; they really took the whole clean-sheet approach to fixing all the [handling] woes.”

Before long, Doug had a full suite of Maximum Motorsports handling components on the car. The suspension geometry was completely changed, and the Fox-body Mustang’s worst traits were resolved. Now the car could hang with just about any competitor in the corners.

Doug had also upgraded the V8 to around 300 horsepower, but he had his second wake-up call during a track day at Ohio’s Nelson Ledges when he encountered some drivers with Corvette Z06s. “They’d put half a dozen car lengths on me on the straights,” he says. “I thought it was now time for more power.”

Turbos were not yet in vogue among the Mustang set, so Doug went the supercharger route without doing much research. A Vortech blower was an undeniable power booster, but it came with its own set of concerns. “It was faster but it got hot, so I put a cooler on it. It was Band-Aid after Band-Aid, packaging and weight,” Doug laments. After a few minutes on track, heat soak would inevitably start to sap power from the pressurized V8, so 500 ponies was a best-case scenario.

Another incident on track, this time at Mid-Ohio Sports Car Course in 2012, was a harbinger of the next big change for Doug’s Mustang: The car shucked its supercharger impeller at speed. “It went through the motor,” Doug recalls.

“I had been keeping an eye on Ernesto Rocco, Chris Griswold-American Iron Xtreme guys [out West] who were running GM-based motors on their cars,” he recalls. “It made me unpopular, but I said, ‘I’m gonna do that.’”

The Heartbeat Transplant of America

“Here on the East Coast it hadn’t been done a lot,” Doug says about GM-powered Mustangs. “You’d see LS motors in Volvo wagons and Porsche 911s, but you stick a Chevy motor in a Mustang and the pitchforks and torches come out.”

Despite the vocal haters, Doug couldn’t think of a better alternative to reach his goal on his budget. Despite all of the options at the time—like the Ford Lightning engine or a custom aluminum crate 302-every possibility just led him back to an aluminum-block GM LS V8.

“I tend to overdo things,” Doug admits. “If you can fix it, you can really fix it.” He traces his perfectionist tendencies back to his aircraft mechanic background. After all, pilots don’t have the luxury of pulling their planes to the side of the road when mechanical woes arise. Anything less than perfect can be deadly.

After doing a proper amount of research, Doug decided on a 416-cubic-inch Mast Motorsports Black Label LS3 with more than 600 horsepower on tap. He was happy before he even unpacked the engine: “The motor came complete from harness to oil pan, and the shipping weight was under 400 pounds, even with the big wooden crate.” Right off the bat, the LS undercut his old supercharged Ford V8 by some 200 pounds.

With such a huge chunk of mass immediately taken off the nose, Doug and some friends were motivated to start shedding even more pounds from the car. The result is what Doug calls version 3.0 of his venerable SVT Cobra. “We chopped the frame rails off, the whole front clip is tubular, bumpers full of foam–weight savings at all costs without compromising strength.”

He was particularly impressed with how easy it was to integrate the Mast crate engine. Its management system only required 28 volts in plus a ground to get it up and running. Doug opted for a 7.25-inch Quarter Master twin-plate rally clutch and a lightweight fly-wheel, further reducing the rotational mass and helping the 7000-rpm LS3 rev with extreme urgency.

The robust Piper cage seems like it would add significant weight to the overall package, but Doug is pleased to report that it doesn’t: The final product weighs just 2700 pounds ready to run, giving it a staggering power-to-weight ratio of just 4.5 pounds per horsepower. Compare that to the latest Viper ACR, which saddles each pony with 5.2 pounds.

While You’re At It

Doug used the major surgery of the engine transplant as an opportunity to fix some other issues he’d had with the Mustang through years. He fabricated the engine mounts and tubular front structure, repositioning the double-pass Ron Davis radiator as far forward and low in the chassis as possible to help achieve his 50/50 weight distribution goal. Reinforcements to what he describes as the soda can-thin firewall helped negate the clutch flex.

Oddly enough, the biggest snag he encountered was finding a pilot bearing that would allow the GM engine to play nice with the Ford transmission. “It stymied me for weeks,” he laughs in hindsight. “You call all these people and nobody knew. I was out there with my micrometer. It turns out an LS7 pilot bearing from a Corvette Z06 works perfectly.”

Doug admits that he turned the dial a little too far toward the track setting during the engine swap; pulling so much weight from the car had rendered it unstreetable. This came back to bite him at Mid-Ohio during his first shakedown run with the new engine. He was so focused on making sure the powerplant worked well–which it did–that he didn’t uncover an improperly machined spindle until he was on track. The resulting vibration ended the outing early. What a waste of a 7-hour tow.

As soon as he returned home, he vowed to get the car street-legal again so he could diagnose the little stuff on the road instead of on the track. “I rewired the turn signals, wired up a horn, registered it, and took it to an inspection station,” he says. “They threw on a West Virginia modified inspection sticker. Now I can drive it and experience any changes I might have made.”

Always Improving

Although nobody is going to confuse this Mustang Cobra SVT for anything close to stock, each upgrade has thrown heaping piles of performance onto the car without sacrificing its inherent Fox-body Mustang style. “Within my financial restraints, I’m really happy with the way it ended up,” Doug says.

Ever the mechanic, Doug’s work on the car will likely never be truly complete. “I’d love to do a short-long-arm suspension on the front, maybe an independent rear,” he muses. “Maybe somewhere down the road it’ll happen.” He’s already extremely pleased with the marriage of GM power and his beloved Ford, though. The car is proving lightning quick and seriously reliable, with engine temps holding steady at 190 degrees even at the end of a long, high-speed track session.

The Mustang is a real visual stunner, too–another result of Doug’s perfectionism. “I get accused of not driving it because the paint is a mile deep, the brushed aluminum,” he explains. “You look at this car and the lines are laser straight.”

Whatever your feelings about merging Ford and General Motors DNA, the final creation is stunning–whether it’s stationary at a car show or clearing its 600-horsepower throat down the straights on track. “Everyone I’ve taken for a ride, it just throws them into the seat,” Doug grins, adding, “once you’re at a speed above where it’s just going to obliterate the tires.”