Compound Boost 2003 Mustang Cobra Twin-Turbo - The Manhattan Project

A boost knob and two Turbonetics Evolution waste-gates are used to control the boost. Turning it up too much can cause serious catastrophic failure.

Compounding 35 psi of boost from the turbos can push 75 psi of boost in the manifold. We don't know of any small-block V-8 engine that can withstand that much pressure-do you?

The only clue that this car is turbocharged is the piping sitting behind the foglight hole in the bumper. Some black paint could solve that problem.

Snow Performance's methanol injection kit was being installed for further testing. Urist said he wanted to duplicate the horsepower we saw on race gas by adding methanol and utilizing pump fuel.

He said not everyone will run $12-per-gallon gas, and the pump gas/meth mix is a viable option.

Inlet temps aren't as high as you would think when compounding the boost. The highest inlet air temperature was 120 degrees, which was recorded during the second leg on back-to-back pulls. The lowest inlet air temp we saw was 99 degrees; the average was in the 101-108-degree range.

In just three pulls, the engine was tuned up, and it rewarded us with this dyno graph. Peak horsepower is a ludicrous 1,188, and the torque's high side was 1,015-at the rear wheels. It's the kind of power that race cars are made of, but this is a little ol' street mule.

We compared the compounded twin-turbo setup to Hellion's standard '03-'04 Cobra kit, which was run on the same dyno. The difference is quite apparent. Not to say the Hellion '03-'04 Cobra kit isn't a stout system-customers' cars have run in the nines. It's just not in the same ballpark as the twin-turbo/ supercharger deal.

Getting the car to stay hooked up on the dyno was a chore. The tires smoked on the rollers, and we tied it down with six straps out back. You can see the dip on all three graphs where the tires spun, recovered, and the power continued climbing. More tuning and better traction will enable this Cobra to crack the 1,200-rwhp barrier. This is the torque curve by itself, and the drop is apparent. If the tires had hooked, the curve would be more linear.