Cobra_R

I heard that adding a new exhaust can cause a loss of HP. I just want to know why it does this, and with an aftermarket exhaust how do you correct the problem. Also if you added a CAI would that lower your HP like exhaust or is it just the exhaust thta does this.

cwsttu

your profile says you have a 88 vert... is that right? if so you have the s4 engine where the 5 and 6th ports operate on backpressure... this means if you get an aftermarket exhaust that is TOO free flowing then your ports will no longer open causing a loss in hp... you need an exhaust that will cause 3psi of backpressure to open your 5 and 6 ports... or just wire them open... terrible low end and nice top end... there are lots of routes you can go, and most if not all are gonna have some kind of down effects... about your intake question... a true CAI will not decrease hp.. now if you slap a cone filter on the AFM in the engine bay then you will be getting nothing but hot air, and trust me (experimented with it before i built my CAI) it sucks lol, engine ran hotter and was not as fast... you can build a box to go around the cone like many people do on this forum.. just search a bit... try to find my thread "finally had time to finish my CAI" my filter is in the fender feeding off nothing but cold air... good luck man

Lawerence

good info

Cobra_R

does a K & N FIPK count as a true CAI?

totallimmortal

no the k&n is just a filter i believe a true cold air goes out of the engine bay, there are also other ways to get your 5th and 6th ports to open withour backpressure do a search to find them one uses rpm activated switches and a electric air compressor and the other uses the stock air pump and a bleed valve