So im in the process of getting my car back NA. I ordered a cheap o high flo cat off ebay to hold me over untill i found an oem cat.


When I bolted up the ebay cat its about 2 inches to short. Does any one have the measurements on what the oem cat length is. I also have a mugen twin loop if that makes a difference and I double checked.. I do have a usdm itr header.


Thanks guys. One day I will have this car running and back on the road again.

 

IIRC its 17". It wont bolt up to the TL though.

 

This is what I have found out.

Starting at the front.
The USDM header (the distance from the head to the cat) is 7/8" shorter than the JDM's header.
The USDM's outlet (connection point, to the cat) is 1 7/8" id (inside diameter) AKA 2" od (outside diameter).
The JDM is closer to (but not exactly) 2 1/2" id.

Moving to the cat.
The USDM cat is 17 5/8" long and both its inlet and outlet are 1 7/8" id, AKA 2" od.
The JDM cat is 13" long and has matching inlet/outlets, about 2 1/2" od.

To the mid "B" pipe.
The USDM is 4" shorter than the JDM version. The USDM has an 1 7/8" id, AKA 2" od.
I don't have a JDM mid "B" pipe, but I can guess that its diameter will match the JDM cat's outlet diameter, of 2 1/2". Why would Honda choke it?

 

sweet thats exactly what i needed thanks man.