JDM vs USDM Exhausts
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From: Santas Neighbor, Canada
JDM vs USDM Exhausts
I remember someone saying that the JDM b-pipe is a different length than the USDM b-pipe. And as such, JDM exhausts do NOT bolt onto USDM ITR's without modifications. True or BS?
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From: Bay Area, FL
Re: JDM vs USDM Exhausts (mafay2)
Re: JDM vs USDM Exhausts
My ctr exhaust for ek9 wouldn't bolt to a usdm cat on the 3 bolt flange side. The studs were spaced slightly wider it was slightly bigger due to the 2.5 cat. My friend had a shorty cat that looked identical to a jdm itr and that is what he believed it to be. Wouldn't fit my oem b pipe. Steve from hmo got me the right one . I see people say they bolted the jdm exhaust on the dc2 and that always has me scratching my head how? Did the 98 spec convert to 2.5 catalytic converter? Then again the ek9 didn't get the 98 spec dc2 header. I know the jdm and usdm are different lengths on the b pipe for the integra, but no one ever mentions that demon 3 bolt flange. Was the ek9 the only one with the bigger 3 bolt flange maybe? I had read they were all the same, but from my experience I saw two oem cats with two different 3 bolt flange sides. One would bolt to a usdm 3 flange exhaust that you see on all 88-00 civics or integras. The other wouldn't. It's been a while but I thought Steve told me ek9 and dc2 used the same cat. I could be wrong. It's been a long time. If they are the same I don't understand how people bolted the b pipe to the cat without modification to one of the flanges. I know I am talking about a different car but the catalytic converter is said to be the same which makes me curious how people are bolting the cat back without the jdm cat?
Re: JDM vs USDM Exhausts
My aftermarket cate is from SMSP and I will someday use it with my JDM iTR header.
To get an idea of the difference in length, between the USDM header and the JDM, I stacked 9 nickels on the SMSP. The JDM header is slightly longer than the USDM iTR header.
To get an idea of the difference in length, between the USDM header and the JDM, I stacked 9 nickels on the SMSP. The JDM header is slightly longer than the USDM iTR header.
Last edited by safedriver; Jan 1, 2019 at 03:46 PM.
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Re: JDM vs USDM Exhausts (mafay2)
I have the same setup and everything fitted perfectly including the muffler tip. I wish my muffler tip would stick out a bit further to avoid blowing soot all over the back of my car.
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Re: JDM vs USDM Exhausts
oh wow, I didn't know about the extra resonator no wonder why my USDM ITR Catback with the JDM 4-1 header is quite loud above 6,000 rpm. Curious to hear an audio clip difference between the 96 and 98
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