Quote Originally Posted by kerrige View Post
Mustang dynos spit out low numbers the same way dyno jets spit out high numbers. Quick question what tires and rims are on this truck? Efan gains aren't an exact science. Really it depends on how much drag your clutch fan creates. The flowmaster is a chambered muffler so it is going to hold you back a little bit especially on the top end. How high did you spin it on the dyno? Did the power start to fall off prior to stopping the dyno pull?
Rolling stock consists of 16x8 steel wagons with 235/70/16 on all 4x's for DD and dyno pulls, what would be a better muffler for max performance and no irritating crack and rasp at the 3k area?