Hey guys, I own an 98 gsr and I'm going to purchase a jdm itr 2.5 outlet 4-1 header. My exhaust is 2.25 custom all the way from the cat to the end. My question is what size cat should I purchase? 2.25 or go with the 2.5. Or should i go with the 2.5 carsound cat and modify to whole exhaust to 2.5 later down the road.

 

I would go with the 2.5" cat, and install a 2.5" -> 2.25" tapered adapter on the B-pipe where it joins the cat. Of course, upgrading to a 2.5" exhaust would be another option, but clearly a much more expensive one.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by djtony5 &raquo;</TD></TR><TR><TD CLASS="quote">Hey guys, I own an 98 gsr and I'm going to purchase a jdm itr 2.5 outlet 4-1 header. My exhaust is 2.25 custom all the way from the cat to the end. My question is what size cat should I purchase? 2.25 or go with the 2.5. Or should i go with the 2.5 carsound cat and modify to whole exhaust to 2.5 later down the road.</TD></TR></TABLE>

exactly same set up i did 3 days ago, i have jdm itr header wit 2.5". 2.5" inlet/outlet carsound cat, customized 2.5" b-pipe no resonator sounds like a shi*, and a jdm itr exhaust.. im gonna have resonator weld on next week coz i dont like the sounds..

 

run open header..haha jk..get the 2.5 to 2.25 for now upgrade later unless youve got money go 2.5 all the way

 

you should talk to dave (smsp) he made me a custom cat, put on all the necessary parts do do a direct bolt up, 2.5 inlet to 2.36 outlet he also put on the jdm donut and welded some flanges to make it a direct bolt up

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