MawneeC5

iTrader: (12)

How far can I stretch say a 3" or a 2.5" Stainless pipe ?

I"m collecting the parts for my header install. The problem is my headers have a 3" collector and my exhaust/cats are 2.5".

I cant decide whether to buy some 3" stainless pipe and then try to stretch my h-Pipe to fit it. Or buy some 2.5 and try to stretch it to go over the headers.

What do you think guys ?

300bhp/ton

With an LS1 you need 3" inlet/outlet CATS else they will be too restrictive. Also you don't want to mount the CATS directly to the headers, you need a bit of space between them. You can by neck down pipes to go from 3" to 2.5" (not sure where but I've seen them, might have been Summit).

MawneeC5

iTrader: (12)

2.5" was what the entire stock exhaust, including cats was made from. When I upgraded to high flow cats..i had to get the right size.

I"m buying pipe to do some custom bends ect...so again..how far can I stretch it ?

rgaynor85

i think u can strectch 2"-3"

gearheads78

iTrader: (29)

You will never get it to expand that far without splitting. You can get it to expand over the same size pipe and thats about it. You need a reducer to go from 3-2.5"

lsx24

iTrader: (45)

You guys covered it all like pros. Now, what else is there left to know.

Tallon535

I've got FLP headers with the adjustable y-pipe. You can either bolt in the cats or straight pipes. When the cats are in they bolt directly to the flange on the header. They have about 3 inches of pipe before it hits the actual cat though.