Exhaust Advice Required.

[Imola-S3]

Hi all...

Looking for some advice on a suitable exhaust system. Mainly what diameter pipe to go for.

My car's an S3 8L APY 1.8T with the following mods:

AirTec FMIC
Badger5 TIP V2
Honda S2000 Cone
3" Downpipe with Sports CAT on to standard exhaust after the CAT.
2.0 TFSI Coil Packs
Forge 007p DV
Forge Actuator
BBT K04 Turbo (Stock with upgraded seals)
N249 Bypass

Currently running at 268bhp on stage 2 from Niki at R-Tech (needs another tune to get the most from newly fitted BBT K04). I don't ever intend on taking this car over 300bhp so please take that into consideration when suggesting the best exhaust for my needs. I'm also looking to watch how much I spend here - And it needs to be as quiet as possible as I hate loud exhausts.
I already have the 3" downpipe - I don't mind losing the Sports CAT because it fails on the emissions with it in anyway! I just need advice on the best diameter pipe etc to support 300bhp.

Any advice would be greatly appreciated.
Cheers

 

[Imola-S3]

Only reason I'm buying a new exhaust is due to the fact that my original one has a huge crack at the back box and it looks like it's going to fall off any minute!

 

[Tom93]

2.5 or 2.75" would be sufficient...

 

[superkarl]

Miltek, can't go wrong. They're 2.75" btw

 

[Imola-S3]

2.5 or 2.75" would be sufficient...

Cheers Tom,
That's what I was hoping.... Can 2.75" be bent in to shape or do they need to have the bends welded in place like the 3" pipes do?

 

[Imola-S3]

Just back from our local performance exhaust fitters - They're going to see if they can do a repair on my current exhaust for now... and have priced me up a 2.5" CAT Back system... they've said a quiet system will set me back £420... and a not so quiet system will be £350. I think for the extra cost I'd prefer near OEM noise. Apparently 2.5" won't be a restriction at all for the power I'll be running.

 

[Tom93]

Thats a bit pricey... Between 250-350 for a custom cat back down here :/ have you phoned around a few powerflow and longlife dealers?

 

[Imola-S3]

These are a Powerflow dealer. Only one in the local area as far as I'm aware.
I'm going to see if they can just replace the pipe from the cat down to the original back box and weld it all up. I'd expect that to be a quicker job that the repair they've got planned for it. I'm down there at 3 this afternoon so I'll see what they suggest. If they can't do the job I'll shop around and see who can keep the costs down.

 

[JonnyDerv]

What downpipe and sports cat do you have that's failing emissions?