Stock cat??


Registered User
Looking at the stock A3 piece the choke point is the initial downpipe.

Would it be totally mad to cut out the stock cat and weld it in the 3" stainless steel decat down pipe.

I know its not ideal but can use 309L stick to weld the stainless tubing to mild steel cat.

Any thoughts on doing this on the cheap?
Don't really want to waste another £100 on a 200 cell high flow cat (that probably won't pass emissions anyway, my last one didn't)

Pic stole from Curts thread