Tom Wilson
December 10, 2010

Tuning the naturally aspirated, carbureted NASCAR engine to Matt's Big Stuff 3 EFI and supercharged Mustang meant a cam change by Leonard. Using a custom grind, he "widened the lobe centers and toned the lift" to maximize in the high 6,000-rpm range. This combo is fronted by a ProCharger F-2, which is nominally pullied to 15 pounds of boost, but up to 20 psi was used on Rocky Mountain Competitive Research's Dynojet. As little as 5-7 psi may be on tap when short-shifting.

If 5 pounds of boost sounds entry-level, consider that big deep-breathing engines with canted-valve heads don't need much more than office-fan blower action to produce windshield-cracking power. We can personally assure you that an emissions-legal Saleen S7 street engine, which is 427 ci underneath canted-valve C3 heads (more or less), makes 750 hp on 4.5 pounds of non-intercooled turbo boost and 1,012 hp at 8 psi. That is with more cubes but considerably less camming than Matt's engine, but you get the idea. Matt's engine was a riot without the blower-pumping boost on top of it is just asking to get hit with both barrels. That's the whole idea here, of course.

To help keep everything in one piece, Matt kitted his engine with his own Snow Performance Stage 3 water/methanol injection. This is the standard reservoir, pump, lines, and nozzles, along with an electronic boost controller and Safe Injection. The controller allows for on-the-fly tuning adjustments and its display tells you what's going on. Safe Injection sets the engine to Safe should the reservoir run dry.

It's amazing what the water-methanol injection does for a supercharged engine. The main point is the mixture is sprayed into the intake manifold, cooling in the intake charge and providing an extremely effective guard against detonation. The water-meth is injected only when the engine is under boost-Matt has the system set to begin spraying at 6 pounds of boost-and with the electronic controller, the injection is ramped up along with the boost.

With Boost Cooler engaged, aggressive boost and ignition timing are possible, along with more rational air/fuel ratios. Excessively rich air/fuel ratios for detonation protection are not needed-the water-meth takes on that job-with the final result being more power. Just how effective the Boost Cooler is can be judged by Matt's combination, which put 907 hp to the Cobra's rear tires-on 91-octane pump gas!

Matt enlisted the House of Boost in Lenexa, Kansas, to make the engine and driveline installation, and add its talented touch on the cosmetics and overall detailing throughout the car. There was a false start along the way when Matt specified a Jerico racing transmission. The ultra-slick-shifting Jerico was no problem, but the grabby four-disc metal clutch that came with it proved impossible on the street. The cure turned out to be a T-56 six-speed and associated short-throw shifter. The stock 8.8-inch rear axle remains.

Matt says he gave the Cobra to House of Boost with "a few blemishes in the front" and they returned the car in its glory as you see it. That meant fitting and painting a Cobra R hood and front bumper, plus cutting the original paint back to a high gloss, along with extra work on those front-end blemishes. Obviously House of Boost put in the hours filling holes in the engine compartment, re-routing hoses and lines, and generally creating a sanitary underhood presentation.

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