Superformance side pipes

[Perf. Eng. Eric]

We just tried a set of our new 3 inch I.D. stainless steel mufflers welded into a stock Superformance exhaust system. Early results on a stroked 351 W looked good on the torque( +27). The horsepower only went up around 10 on the first test, but the air fuel with the old mufflers was around 12.9 to 1, and with the new ones ,it jumped up to 14.6 to 1. The stock Superformance muffler is only around 2.250 on the I.D. We have allways felt on our higher H.P. motors, the pipes were a big factor on the H.P. loss from our engine dyno, to our chassis dyno. I think Tuesdays dyno results will be interesting. I will be changing jets and timming in the morning. I think the big blocks will really wake up with these new mufflers. When the testing is done ,we will re-ceramic coat the side pipes back to the original color, and the system will look stock. The mufflers are the same length and O.D. as the stock ones, so no one will know you have made the change. Oh, and the sound is much deeper, and I love it.