im looking at the apexi gt spec header. today i bought the apexi gt spec catback for my 99 ls. while lookign at the gt spec header it says "for jdm itr only". even though the itr exhausts fit the ls and the ls exhaust fits the itr would the header still fit the ls?

 

I don't think a header intended for a VTEC engine will fit a non-VTEC LS without atleast some modification. Also, the JDM ITR has a 2.5 collector at the end of the header, so you'd need a 2.5 inch catalytic converter to fit it. Your car probably has a 2.25 inch catalytic converter strapped underneath.

edit: made some spelling errors on the first try

 

alright so i would need a 2.5 inlet cat and a 2.5 outlet right? could someone please give me a link or give me a brand that would fulfill my needs? thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CaptivaBlue &raquo;</TD></TR><TR><TD CLASS="quote">I don't think a header intended for a VTEC engine will fit a non-VTEC LS without atleast some modification. Also, the JDM ITR has a 2.5 collector at the end of the header, so you'd need a 2.5 inch catalytic converter to fit it. Your car probably has a 2.25 inch catalytic converter strapped underneath.

edit: made some spelling errors on the first try</TD></TR></TABLE>the vtec doesn't matter in terms of header fitment (94-01 non vtec headers fit 00-01 gsr's without modification). you are correct though, with this header, a 2.5" cat or test pipe will be needed.

go to kteller.com, he welds the flanges on carsound cats for you..

 

sweet. also do high flow cats help u pick up any more power?