Ahmet

Looking into different high flow cats, I have a custom fabricator and am working on locating high quality, less restrictive cats. Anybody know the exact pipe diameter?

Thanks in advance.

AudiOn19s

2.25". All 996 exhausts are the same diameter.

It's actually 55mm metric tubing which is near impossible to find over here. 2.25 is as close as you will get.

Ahmet

Thank you so much for the detailed info! I suspected they were the same as other 996s (head port size looks quite similar at a glance), but good to know for sure.

KOAN

I think the Europipe is bigger...something like 3.0"

Andy, are you going to MORPCA at Mid Ohio in April?

AudiOn19s

Euro pipe is bigger, so is Cargraphic in the R-system and the custom system that Charles D builds. The key to all of them is they are larger from the header back, not just the muffler. They all make good power!

I am signed up for MOR in April. Need to get motivated and out in the garage to get the car put back together. Wheel bearing replacement turned into a lot more maintenance stuff and it's currently in a million pieces.

Ahmet

I would only be replacing the cats, got an intermittent efficiency code, but it hasn’t come back... A lot of 996 GT3s seem to do this, odd...

Anyway, I’d love to join you guys at Mid-Ohio (never been), but it’s a bit of a haul from NC.

Thanks again for the helpful info.