Building a 1,627 HP 2007 Ford Shelby - 7-Second Screw

Horse Sense: We'll admit we're terribly jaded, but when Mark fired up his Shelby in the Accufab shop the incredibly delicious sound tickled our pleasure center. Good thing, too, because if the bright bouquet of methanol fuel, the crackle and thunder of 1,700 hp doesn't do it for you, get your pulse checked. It's difficult to believe this beast occasionally prowls the streets.

Mark Meiering is a successful house painter from Albuquerque, New Mexico, with a thing for fast street cars. It's understandable. After a week of evenly applied Sandalwood Beige, any of us would look forward to a heavy-duty cruise scene on Saturday nights.

But as you all know, by the time a car makes it to these pages there's typically more to the story than boy meets blower and beats Camaro. In this case it's the familiar tale of a little was fun, so why not a whole lot more? Or, how to run 7s in three engines and two blowers.

He bought his GT500 Shelby new in 2007 and has "done a ton of street driving" with it. He says it was stock "about two weeks before I got bored with it," and he and a friend bolted on a Kenne Bell 2.8-liter screw blower in about 10 hours. This was KB's first generation Shelby blower. "It really woke up the car," Mark explained.-

The combination lasted about six months before a tuning issue rattled a rod through the side of the block. There was no warranty love coming, of course, so Mark had to paint a few extra bungalows before latching onto the then-new Ford GT-based aluminum 5.4 block to build a second engine around. The compression was set at 10:1 for a little extra punch and the 2.8 blower was put back on. Later Kenne Bell released the 3.6 blower and Mark had to have that. This proved a happy combination, or as Mark put it, "That was a fast street car! It was happening."

Of course, Mark was always fiddling with his by-then 10-second Shelby, and among other things, he tried a set of more aggressive cams. These were causing some issues when a friend of Mark's was referred to John Mihovetz at Accufab as a hot modular expert who could probably sort out the problem. This isn't bad advice, as regular readers may recall John has a twin-turbo 4.6 program he's developed to 2,800 hp and nearly 5-second timeslips in a tube-frame Cougar. The result was John built a motor for Mark in 2009 that made 1,100 flywheel horsepower, which you'd think would be enough. We documented this engine as part of a Kenne Bell 3.6-liter supercharger test in 2010 (Kenne Bell Twin Screw Supercharger - Bell Curve - 3.6-Liter Twin Screw). As this was the same engine that's still in the car the blower article gives some good nuts and bolts background if you're interested.

By that time, Mark was already circling moth-like to the drag racing flame as the only place to wring out this sort of "street car" is at the dragstrip. The Mihovetz engine with its Ford GT block, heavily prepped GT500 cylinder heads, and top-notch internals were ready to make truly serious power, and Jim Bell at Kenne Bell had become interested in the program as well. The goal was set to make it the first belt-driven GT500 street car in the 7s, a feat performed at a hot and humid test session at Fomoso dragstrip in Bakersfield, California, last September with a 7.817-/180.57- mph pass. Considering some of us on staff remember when it nearly took a Top Fuel dragster to run these numbers, lobbing a steel-bodied Mustang with a full interior down the quarter-mile in less than 8 seconds is fairly mind-blowing.

Key to making serious horsepower is fuel. It absolutely must be high-octane for detonation resistance, and like many today, Mark found alcohol just the stuff. For the most part this means E85 from local gas stations, but just as we were documenting Mark's ride, John Mihovetz switched the car to methanol, like his pure drag car runs. The two fuels are somewhat interchangeable. Yes, they do require different tunes, the methanol is horribly corrosive and requires careful attention to material compatibility throughout the fuel system, plus it requires even greater fire-hose volumes than E85. But it also has cooling and burning properties much closer to E85 than gasoline.

Supplying the necessary fuel volume is far beyond the capabilities of any bolt-on fuel pumps and lines. Today the Shelby wears a fuel cell and cable-driven Waterman Racing Components fuel pump. A belt drives the external dry-sump-system oil pump, with a cable running off the back of the oil pump to the Waterman fuel pump at the rear of the car. While capable of resetting your concept of how much a fuel pump can cost, the Waterman pump has proven bulletproof and easily capable of slaking the alcoholic 5.4's thirst. It's even silent, a plus for street operation.

It also takes a blower. Kenne Bell has kept the program sourced with 3.6-liter, liquid-cooled units, the better for KB to develop its largest blower currently (there's always a larger one coming…). We won't re-plow the 3.6 story here, but will point you toward the photos showing the low-restriction inlet developed on Meiering's car. It's key to getting 1,700 hp worth of air into the engine. We'll also note Kenne Bell's 3.6 Shelby blower kit is pretty much a bolt-on on Mark's car. Liquid-cooling was used, along with boost in the mid 20-psi range.

As for the core engine, it's a 5.4 using the Ford GT block—3.555-inch bore x 4.165-inch stroke—and heavily prepped GT500 cylinder heads. It's mainly the work of Fred Grouchulski at Mihovetiz's engine shop Accufab Racing Engines. While it does rev, this is no flyweight small-block, but rather a bulletproof, built-to-take-it drag motor jammed with the knowledge and hand-detailing it takes to prevail at these power levels.

To get an idea of the mechanical robustness, the engine specs include a billet Bryant crank and John's special Manley Pro Series connecting rods. Fred calls these "spark diesel rods" because they're about three times beefier than gasoline rods, hefting in at 1,900 grams worth of bobweight. Equally stout are the custom JE pistons with their 0.250-inch-thick skirts and ditto on the piston pins. It's all good to 3,000 horsepower says Fred.

Taking advantage of the high-pressure air at the base of the windshield, the big Kenne Bell aspirates via one of the shortest, least restrictive inlets possible, built by Hogan Manifolds. The idea came from a “mile car” John Mihovetz worked on, and was pushed along by Mark’s engine sucking the previously fitted Ford GT inlet tube flat at full chat. Underneath, the blower sits on the usual Kenne Bell adapter plate/charge cooler and stock Ford intake.

With the Harwood fiberglass hood attached, the twin 105mm Accufab throttle bodies show their unrestricted access to the atmosphere. For street driving, Meiering fits a custom air filter over the still drive-by-wire throttles to keep out the birds and small planes.

Using a Ford GT front cover allowed Meiering to ditch the power steering, which in turn allowed a shorter, more stable supercharger drive belt. The 10-rib Kenne Bell arrangement, which includes a Thumper tensioner, has proven trouble-free.

There’s plenty of jewelry hidden under Mark’s Shelby. The billet Dailey Engineering oil pan/stud girdle and pump assembly is something John runs on all his modulars. Another Dailey benefit, all the oil lines are machined into the pan, eliminating external oil lines.

Engine management has been something of a journey for Mark. From tuned stock hardware, he moved to Big Stuff 3. When John took over the engine and tuning, he wanted Motec controls like his own race car, so this Shelby was re-wired for Motec, which it currently runs.

Integrated into the Dailey oil pan is the belt-driven, Roots-type Dailey oil pump. Only two oil hoses are required to/from the cooler and Petersen oil tank. Another plus, the Dailey pump is designed to accept the cable drive for the Waterman fuel pump so integrating those two is a plug-in affair.

The hydrant-like fuel volumes required by high-powered alcohol cars tax the capability of electric pumps, and Mark found the pro-racing-oriented Waterman 1320 pump was the answer to popped circuit breakers and dead batteries at half track. The cable drive from the oil pump gives a wide latitude in mounting. Meiering chose under the fuel cell; here the cable drive is visible coming from the top of the photo. The pump is anodized red and black; the Magnafuel filter natural aluminum. Fuel supply is no longer an issue.

Meiering found dry-sumping a must at the 1,200hp level, as the 5.4 was snacking on bearings—he never lost an engine but dry-sumping cured all oiling issues. The harmonic damper is “the biggest ATI damper that will fit.” It requires some machining of the Ford GT front cover.

If the big Kenne Bell blower and lawn sprinkler fuel injectors are stuffing the engine full of air and alcohol, then it makes sense the headers must be huge to get it all out. Mihovetz says you can’t get them big enough; these custom 21⁄8 to 21⁄4-inch stepped primary headers are as large as will fit and still aren’t enough. For cruise nights, Mark fits four mufflers in a vain attempt to avoid choking the exhaust flow. Muffling this monster is a crime as its exhaust note is absolutely prime.