As for performance differences between the 2, I'd say around 1-3HP tops. A catback only increases the diameter all the way throught the exhaust and reduces the bends. The stock piping on the P5 is around 2.2" and you really don't need a cat-back exhaust. There is only 1 bend that isn't a true 2.2" on our stock systems.
APEXistud - So, lets use this for example... The racing beat catback utilizes 60mm piping where-as our cars stock system uses 55mm... What kind of difference in performance is that? Like I stated earlier 1-3HP tops! I know I can't notice a 3HP gain. Now, if you plan to go past basic bolt ons and on to forced induction, a 3" pipe is ideal.
As for performance differences between the 2, I'd say around 1-3HP tops. A catback only increases the diameter all the way throught the exhaust and reduces the bends. The stock piping on the P5 is around 2.2" and you really don't need a cat-back exhaust. There is only 1 bend that isn't a true 2.2" on our stock systems.
Did you personally measure the inside diameter of the piping? Also, what I meant by 1-3HP is the difference between the gain of an axle-back and a cat-back exhaust. Besides, how much performance difference is 4.7HP(Racing Beat gain)? I'd say not significant enough to notice.
Did you personally measure the inside diameter of the piping? Also, what I meant by 1-3HP is the difference between the gain of an axle-back and a cat-back exhaust. Besides, how much performance difference is 4.7HP(Racing Beat gain)? I'd say not significant enough to notice.
I have not, however a member of the boards that hasn't been around for awhile, some may remember Traveler, measured inside and outside diameter of the exhaust from the first cat, all the way back.
He then made his own exhaust that worked quite well. He made a short header that kept the first stock cat, and then a new connecting pipe, etc...
