The addition of the RoushCharger and its new ECM tune generated 370 hp and 350 lb-ft of torque to the rear wheels. Air/fuel ratio checked in at about 12.9:1. This is with 5 psi of boost, which is the only way the kit comes.
At $5,699, the RoushCharger is not the most inexpensive supercharger on the market, but as Crazy Horse Racing's owner Chris Winter put it, "This is the most well-engineered supercharger kit we've ever seen."
Which should not be unexpected at this price, especially considering Roush does a ton of OE-engineering for Ford and numerous other car companies.
What was unexpected was what appeared to be a severely rich issue we encountered after the dyno pulls on our way home. Everything was fine until we were about 20 miles from the shop, when the car began stumbling and losing power.
After contacting Roush, we were informed of a spark plug fouling issue that they believed they had solved with the latest ECM tune they had sent us. A new set of spark plugs did not resolve the issue, which left us scratching our heads. Until, that is, the folks at Roush asked if we had torqued the spark plugs, per the directions. We sheepishly admitted we hadn't. In went yet another new set of plugs and this time we properly torqued them down. Strange as this sounds, it completely cured the problem. The ride home was uneventful, except for us enjoying the monster's extra 120 hp.
In our next installment, we plan to install and test the Roush Stage 3 front brake package. This will cure the car's biggest deficiency on the road course, which was the stock binders. Then we'll have to say "Adios" to the Stage 2 Stang. They're gonna have to pry the keys from our hands.