How Much Horsepower Does A Performance Exhaust Add?
How Much Horsepower Does A Performance Exhaust Add? MagnaFlow, an aftermarket exhaust manufacturer, says that its customers can expect horsepower gains of around 10 percent (which is a pretty commonly-quoted figure). How much HP does cat back exhaust add? In general, expect a 2-5 percent increase in torque, horsepower, and fuel mileage. Does a performance