Since boost was part of the plan, we ditched the plastic factory manifold in favor of Trick Flow's Track Heat manifold (PN TFS-51811002; $799.95) with a stealthy black-powdercoat finish. The Track Heat is a direct-replacement manifold that trades the bottom end for more gusto at higher rpm. Our version uses the stock-style round throttle body, and it offers an operating range of 1,500-6,500 rpm. If you step up to the twin-blade-throttle-body-style upper, the useable range shifts from 2,000 to 7,000 rpm, so you definitely want some robust valvesprings if you're going to wind it that high.
We started making some headway as Ray wrapped up the intake swap, added ACCEL's upgraded coils, and dropped on the cam covers. We're almost ready to drop the car back on its engine.
Before doing that, however, Ray made the wise choice of adding a SPEC Stage 3 clutch and aluminum flywheel to harness the turbo Two-Valve's newfound power.
We had to go back to the office to work on some other stories, so we weren't around to see Ray strap on the Hellion turbo kit, but longtime readers have seen us cover turbo installs before-swapping headers, attaching plumbing, tapping oil pans, and so on. Ray happened to have a used T-76 turbo laying around and got the rest of the kit from Hellion. Though it kept the costs down on the project, it did prove to be a mismatch because the 76 didn't start pulling hard until 4,500 rpm. Ray says the 66mm turbo is a better choice for a street car since it brings on the boost earlier. The combo produced about 15 pounds of boost and really helped us double our baseline power numbers.
On The Dyno
Working to get just the right tune for this combination, Ray found that the best mass air combination is a JLT housing from one of the company's popular cold-air kits, fitted with a Ford GT mass air sensor and augmented by a DiabloSport MAFia. Ray says this combination and a few hours of tuning work yielded the best driveability he's seen with cams and this level of boost. As you can see, we gave up on the bottom with free-flowing heads, cam, and intake. Of course, once the boost builds, look out.
Click here for the two-valve Mustang buildup dyno chart