Since receiving the '05 Roush Stage 2 Mustang last summer, we've logged over 7,000 miles on it and have enjoyed every one of them. Normally, we have press cars for a week or two and that's it, so when we noticed the Roush had been hanging around for three weeks, and then two months, we knew something was off its axis.
Bottom line was, Roush wanted us to experience its car the way the typical owner would. Let's face it: You can only learn so much about a vehicle in seven days. Ultimately, we have to extend our compliments to Roush and its engineers. Except for the drone of its exhaust at certain rpm (and the exhaust tip that someone pilfered), our relationship with this car has been a delight. Unlike some temperamental tuner cars with bone-jarring rides, the Roush has exhibited no bad manners. The ride is as smooth as factory stock, yet the grip is akin to a race car. The body kit, wheels, and stripes get stares and compliments from bystanders wherever we take it.
While we have appreciated the extended seat time in the Stage 2, our main gripe has been the stock 300hp 4.6 under the hood. When you drive something that screams, "Race Me!" (at 40,000 clams, no less), you'd better have more oats in the feedback than Dearborn supplies. The horse-power junkie in all of us wanted to strap on a supercharged Roush Stage 3 Mustang and see what it has to offer.
Then, the powers that be at Roush decided to have us upgrade the Stage 2 to its big brother's specifications. That's right, we're going to mod a press car and get away with it.
Here's what makes the Stage 3 Roush a thoroughbred. The supercharger system retails for $5,699 and includes everything you think the factory would have included if it was selling it over-the-counter. It's that inclusive.
While we'll be foregoing the small blower pulleys and custom ECM tunes, what we will have once we're finished is an emissions-legal, fully warranted package that should improve on the Stage 2's already stellar foundation. Later installments will see the Stallion fitted with Roush's Stage 3 brakes, its lighter (by 11 pounds each) forged aluminum wheels and shifter.
In this installment of the Mustang's transformation, we installed the RoushCharger, which is an M90-size, Roots-style supercharger that pumped up this Mustang's power output from a stock 251 rwhp to 370 rwhp. Torque also improved from 275 lb-ft to 350. It should be noted that the RoushCharger is available over-the-counter to anyone with an '05-up Mustang. Best of all, it will not, according to Roush, void your precious factory warranty.
One thing we noticed prior to our baseline runs was that the passenger-side rear brake caliper seemed to be hanging up for some. The rotor was actually puffing a bit of smoke after each dyno pull, so we may have lost a few horsepower there, but the issue was resolved prior to thrashing the Roush with the supercharger.