S3: Racing cat and downpipe?

[Damo S]

My S3 is stage 2 tune (fmic, intake, remap) but the exhaust side is completely stock. Would it be worth putting in a miltek racing cat and downpipe to help it flow a bit better at higher rpm? (but keep the rest of the exhaust standard).

I don't really want to do the exhaust as well because its a lot of money and I don't really want any more noise.

 

[larbel]

Downpipe is actually one of the requirement for stage 2 from many tuners. Even a sports cat would helps greatly as the stock cat and diameter is a major restriction. You'll notice the rpm climbs more freely and boost builds a bit faster. And with sports cat (HJS Euro 6 in my case) the exhaust note is already way deeper than stock, for me, I wouldn't even go with res delete let alone exhaust as it's already louder than stock...

 

[Damo S]

Mine was a custom stage 2 tuned to the mods I had, rather than being one of those out of the box types for a defined set.

I remember from previous cars that a DP and decat allowed the turbo to spool up much quicker, typically about 500rpm earlier when it starts to fly, and like you say feels a bit more lively at high rpms.

Sounds like it may be worth a punt at some point