ok, my friend just installed his JDM 4-1 header with gutted stock cat.... now his car sounds raspy and annoying. he got cat back tanabe RM.

before with no gutted cat and regular DC headers it sounded deep and nice.

is it like this with your R too?

 

 

so, its like that when its gutted?

 

YES, it will soudn like CRAP

 

so let me get this straight, you connected a 2.5" JDM header to a stock 2.25" cat...why bother changing the header???

 

My thoughts exactly. Tell your friend to do it right and get a 2.5" Carsound cat and the car should sound fine...

 

My question is: does the stock cat flange fit the 2.5" header flange? Isn't it going to leak?

 

it's used or new? probably have hole on it. sounds really bad, but souldn't be like that, but DCs are really nice for me.

 

thats what happen with my few customers teg with Tanabe Racing Medalion, they sounds farty when you use any 4-1 configuration header.

 

Don't gutt a cat.

The stock cat is 2" as is the stock header and any USDM header. Get rid of the Tanabe bottle neck when you install your 2-1/2" cat and you'll pick up some more power.

Tanabe with 2-1/2" ID x 2-3/8 OD adapter along side the Tanabe bottle neck which is 2" OD x 2" long


Adapter B pipe flange ID vs as received Tanabe. A 2-1/2" Car Sound Cat was used for 1-2 weeks with the as received Tanabe exhaust, notice the exhaust deposit on the flange face due to the mismatch of the IDs

 

good pics..thanx

 

carounds 2.5 inch... makes the difference

 

damn, you all beat me to it. 2.25 cat

 

i just put a jdm header on my car with a test pipe and it sounds like crap too. However, when vtec engages, it sounds really mean