At just 6 psi of boost, the rwhp was an impressive 552 rwhp and max torque was a robust 60
The engine tune was easy--it was actually the transmission functions that needed most of the attention. Rochau offered some insight into tuning the MSD Mustang. "The 2011 5.0L Mustangs have wide-band O2 sensors in the front location, which is really cool because you can go into the computer and command an air/fuel ratio at WOT. But in a turbo application, you don't command the same air/fuel ratio as you would in an N/A or supercharger because the sensors see increased backpressure due to the turbos. You have to make sure the MAF functions are right on par in order to effectively use the wide-band O2 capabilities."
The Mustang was tested on MSDs in-house chassis dyno, a SuperFlow unit that reads similar to a DynoJet eddy-current chassis dyno. The initial dyno runs were made with the front fascia off the car, and according to Urist, they've tested the system with and without the cover only to find no change in power. Our speculation is that since the boost is limited to just 6 psi it didn't matter. The turbo will work harder to achieve that same 6 psi with the front fascia on.
After some initial runs, we ran into one problem. The MAF sensor was maxed out despite a 4-inch-diameter sampling pipe. Urist worked with Pro-M to get one of the first MAF sensors designed for use on the 2011 Mustang 5.0L. The Pro-M Wave MAF sensor is frequency-based and can be used in all '11-and-up Ford products. It supports anywhere from 800 flywheel horsepower to 1,400 depending on the diameter of the tube.
The larger capacity MAF sensor solved the problem, and Rochau and Urist were back on the dyno looking for maximum power out of the base Hellion kit. This time the nose was back on the car for final chassis dyno-testing. The boost was fixed at 6 psi and the automatic-equipped Mustang unleashed a best of 552 rwhp and 605 lb-ft of torque at the wheels. That was through the factory 6R80 automatic and on pump gas.
The car continued to impress us on the street as it pulls cleanly and nicely when jumping on the pedal. We were even impressed with how quickly the 64mm turbo spools and generates boost--no lag in this combination. Unfortunately we didn't get any track numbers, but we think it's capable of pushing the car into the 10s with ease on slicks or drag radials.
"This system is the ultimate solution to adding horsepower to a 2011 Mustang GT because we can adjust the boost from 6 to 25 psi without changing any parts on the kit," says Urist. "It doesn't need any extras to make more power. All you need is the base system--no need to change exhaust, pulleys, throttle bodies, or anything else. When you want more power, just turn up the boost."
The car we sampled was an auto-equipped ride; Urist sent us info on a Hellion-powered six-speed manual car. The 2011 Mustang GT was equipped with a ball-bearing Turbonetics HP64 turbo just like the one we covered on these pages. Naturally the manual transmission netted more horsepower at the tires, and it spun a DynoJet chassis dyno to an impressive 640 rwhp and 748 lb-ft of torque. Boost was the same 6 psi, and Dave Rochau of Motiva Performance handled the custom ECU tune using SCT software.