Our 4-1 header design was chosen to allow for superior flow. Our 1.75" diameter runners merge into a 2.5" outlet. This allows our header to mate up to most after market over pipes while still allowing it to bolt up to the factory exhaust. The header is also built with 1/2" flanges to really beef up the quality and insure no warping will occur from heat.
Our Stage 1 bundle utilizes our best selling unequal length header
paired with the popular Motiv Concepts Overpipe. These parts compliment each other perfectly, both using a 2.5" 2 bolt flange.
Fitment, quality and performance are all benefits of this quality pairing. You
can expect superior exhaust flow and noticeable gains.
Stage 2 steps up horsepower by incorporating everything from Stage 1 package, and adding in an upgraded Frontpipe from Motiv Concept. This high-flow catted Frontpipe allows the exhaust to exit the system smoothly by using the same 2.5" piping diameter. This combination is sure to give you that clean sounding boxer rumble you are looking for, while keeping the noise levels reasonable