i recently put my turbo kit in my 99LS. it was a GSR kit and the downpipe doesn't reach the cat, so i'm running open downpipe right now. i was planning to get a test pipe and extend it. i wanted to know if anyone knows how much longer the cat would need to be or have any other suggestions.
i have a greddy GSR dohc kit with a TD05-18g on a LS.
if you need any other info, just ask.

thanks guys

 

anybody? i'm now thinking of just going to a muffler shop and have them extend it.

 

tape measure knows all...

 

just take it to a shop that does pipes. Make sure though when you get an extension made for the downpipe, it doesnt taper in size, and that its atleast 304 (preferably 321) steel because the downpipe (also the exhaust manifold) sees some pretty high EGT's when running on a constant boost level.

 

thanks for the advice