cat woes

greenninja · Post by **greenninja** » Mon Oct 13, 2014 10:40 am

Thanks for the info scott, after looking for a correct size cat all weekend i think i am just going to shorten my exhaust system by a couple of inches and use the euro cat for fifty quid. A shame but 700 quid for a new cat is not an option.

Scott560 · Post by **Scott560** » Mon Oct 13, 2014 9:28 pm

yup, the new cat has worked fine and i have no worries. Even passed emissions convincingly.

deffo down on power and noise though

greenninja · Post by **greenninja** » Wed Oct 15, 2014 11:09 am

Hi guys, before i take the cutter to my exhaust to make this cat fit i just wondered if a 4th gen cat will fit the 1997 5th gen vti. As they are the same length. Does anyone know is this will fit ? Also what diameter is a 1997 vtis exhaust system. Trying to source a decent sleeve. Many thanks

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Wed Oct 15, 2014 12:25 pm

Merlin posted a link earlier in this thread to the wiki pages, that shows on the relevant info on the various cat lengths.
If the length is the same, then it will fit - the exhaust parts are otherwise interchangeable (flanges the same etc.)

Noting the comment above that the pattern part cat has resulted in the car being down on power, I would once again strongly recommend that you just get a used cat from one of the cars being broken on here, rather than spend (more) time and money butchering your current exhaust for something that will then make your car run worse!

However, it is your car, your choice.

greenninja · Post by **greenninja** » Wed Oct 15, 2014 12:35 pm

I am on the hunt for a second hand cat, have sent 2 pms on here but no reply as yet. My car def feels a bit down on power with a gutted cat and doesnt sound as nice when driving hard. So a 4th gen vti cat will fit a 5th gen vti auto. Thanks for the info guys

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Wed Oct 15, 2014 2:23 pm

Just one more thing to note - having said the the exhaust parts are interchangeable provided the lengths match, just so it doesn't take you by surprise... If you're mixing/matching a UKDM downpipe to a JDM cat, you might find there is a slight difference in the alignment of the studs on the flange on one part, to the holes on the flange of the other part.
The misalignment is very very small and can be very easily sorted by opening out the holes slightly (either file or drill out to a larger diameter) without any problems.
There are quite a few people on here that have done it.

Example of a 4th gen UKDM downpipe to a JDM cat below so you can see what I mean;