I have a JDM EG6 civic SIR2 that i have recently put a JDM Integra Type r engine in to.
I got a down pipe with the engine that is over 50mm final bore. I need a cat so i can use the flange to make a de-cat pipe so i got the breakers to send me an old cat. however, the one they sent was too small a bore but they said it was off a teg type r. I got them to send me another downpipe so I could compare. This one measured 42mm bore and they insisted it came off the teg.

Basically, what size should the final bore be on a teg type r downpipe. I will obveously use the larger one but still would like to know what is going on.

Also, I ordered a Supersprint stainless header for the teg type r and it had a 48mm bore!! What does the likes of DC sports use???

Sorry for all the q`s but it will be handy to know.

Cheers in advance.

 

The "downpipes" that you received are most likely from a USDM or other version of the ITR which use smaller header collectors/cats than the JDM version.

If the SS header you ordered only has a 48mm collector, you will probably want to order a different header instead. DC Sports offers a JDM 4-1 header with a 2.5" (~64mm) and there are many other headers with 2.5" collectors that may be available to you, including the stock 98-spec. Honda ITR 4-1.