I feel kinda dumb even asking this, but could someone tell me the stock length for a 1993 Si hatch catalytic converter?

I put on my new Apexi WS2 exhaust today, and there's about a 1.5-2" gap it seems between the B-pipe and the cat. I got it all together, but it's putting a lot of stress on the exhaust hanger bushings cause it's pulling the exhaust forward. So much so that the B-pipe is hitting/rubbing in several areas and I'm not going to drive it around like that.

The cat appears to be oem, but the bolts that were holding it on definitely were not, so it makes me wonder if it may have been replaced (The header is definitely oem, but may or may not be from the car originally because the front brace that hold the header to the block is missing the bolt that bolts into the block...just some add'l info there). The length of the one I have now is 15 1/2" from flange to flange on the outside edges like this:
Measured from this point --> |-====-| <-- to this point. (I apologize for the crude depiction).

Anyways, I've seen a couple places while searching that states the USDM cats are 17" in length, but I can't find definitive proof that it's true. If so, that would indeed be my missing length that I need.

I appreciate any insight given.

TIA

 

Anyone?

 

FWIW, I just measure the one I have waiting to go into my EM1 and it's 16 5/8" flange to flange.

Could probably do a bit of digging around hondaautomotiveparts.com and see if the part numbers are the same between the cat for your car and the 99-00 Si. If it is, then 16 5/8" is your answer.

 

Good looking out man, I'll definitely check it out. I found this yesterday from this post in the FAQs (https://honda-tech.com/forums/showpo...0&postcount=40)
So if that's the case, then yes, that's my missing length.

 

Well, according to hondapartsunlimited.com the part number for my cat is 18160-P06-Y41 and the part number for a 99 Si cat is 18160-P2P-A00.

However, the difference might be that I don't have an o2 sensor in my cat like ob2 cars do.

 

I will measure my 92 EH3 tomorrow for you

 

Thanks buddy, I appreciate it!

 

Hatch cat is a little shorter than coupe/sedan, by about an inch IIRC, but it still doesn't explain what's going on here, although you could use a coupe/sedan cat to gain some length.

 

Yeh it is odd, I've never had a cat-back exhaust with this much fitment issues. I check and rechecked the installation of the piping and it's all correct. I double-checked the box and it states it is for an EH3 HB w/ a d16z6, so I'm at a loss for right now.

 

My 92 EH3(Civic Si Hatchback) has a cat length of 16 5/8" outside of flange to outside of flange. Hope this helps.

 

Thanks that helps a lot! Sounds like mine is short by an inch or so, it looks oem, but maybe it came off another honda or acura, who knows! I think I'll just take my to get lengthened at the muffler shop and call it a day.