Straight Pipe Or Cat For A Non-Turbo

[EagleTalon1991]

I currently have a straight/test pipe in place of my cat. I have heard rumors of loosing alot of performance from having just a test pipe. Is this true? My setup at this point in time is pacesetter headers to a test pipe to the stock downpipe to the exhaust. Cheap but every little bit counts. Is it true that the straight pipe looses power? Or does it help? Should i buy a highflow cat?

Jeff

 

[MetalliHawk]

Get a highflow cat, unless you want a raspy exhaust. I had a testpipe (still do if you want it $20 shipped) and it sounded like ass. Went with the cat and it took it all away. BTW, I've got an OBX header and 2.5" exhaust, megan muffler. Hope this helps

 

[EagleTalon1991]

Well my exhaust doesn't sound bad nothign specail but it sounds pretty good i was asking performance wise if no back pressure would cause a loss of horse power.

Jeff

 

[anubis]

damn it. i just spent an hour typing up a really nice, detailed answer to this question. i somehow had to log back in and it screwed everything up so now you get the generic answer:

with a header, the straight pipe will not have a negative effect on performance. having the stock cat-back still on there is killing you though. get a good mandrel beant cat-back with a high flow muffler. that'll maximize the power gains of the header you have on there. then start saving and get a quality high-flow catalytic converter (to stay legal and not pollute the air that you and i have to breath). if you want, i can explain why later. i don't feel like re-typing my essay on scavenging and fluid mechanics