Where to get a catalytic converter? (5g 2.2VTI)

[wurlycorner]

but there isn't really a test for it being blocked

You can use an IR temp reader to check temp differential front-rear of the cat.
If it's free-flowing, there shouldn't be much difference. If it's blocked, rear will be significantly cooler.

If it's a pre and post O2 sensor car (ludes aren't so this comment is effectively just wasting the internet - sorry!) you can pop the sensors out and put a pressure gauge in their place to check the pressure either side - same as temp, shouldn't be enormous difference unless blocked.

[stinkypaul]

I had a feeling that might be the case, yeah I do still have the heat shield. I'm starting to consider the option of replacing the entire downpipe as well as the cat, however there is a complication here too... A while back I fitted a full powerflow catback system which I got cheap second hand, but it turned out to be for a JDM model, so it was slightly too short to reach my cat. As my downpipe/flexi was a little worse for wear, I decided to have that cut and lengthened instead, which in turn moved my cat further rearwards to meet the powerflow system.

So here is the new question, can I just buy a JDM H22A5 downpipe with a new cat to fit my current exhaust?

Appreciate you've probably got this sorted now, but that's similar to my situation. To make everything fit I have a downpipe from one model, a cat from another and a cat-back stainless design for a different model again. Fit's perfect though

Measuring is tricky. I have the following on file for when I needed to last replace my downpipe. (I know that's nerdy). However when I next need to change or fix it, I'll either have custom parts made or weld it myself.

BM70450 845mm lambda before the flexi, pipe before and after flexi is long, hanger after flexi (H22A2) * (£55, available) 93 - 96

BM70496 660mm Lambda after flexi. Pipe before and after flexi is short, hanger after flexi (H22A5)

BM70630 730mm Lambda after flexi and close to flange. hanger after flexi (H22A5, H22A2)

BM70404 880mm lambda before the flexi, pipe before and after flexi is long, hanger after flexi

--- Cats ---

BM90784 392mm ** 97-01

BM90790 252mm

BM90723 357mm * 93-96

I think I went for the BM70450 and BM90784 which worked for me, but you'll have to measure up your pipe.

The stock cat flange bolt holes didn't quite match up to my stainless cat back, I had to open up the holes on one side.

[vanzep]

link to oem cat sizes for 4th and 5th gen in knowledge base on forum:

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