New exhaust system help. What spec?

DJ_Troopa

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Morning everyone!

Looking to get my new custom exhaust next month but i have a few questions!

I'd like a turbo back exhaust system with a 100 cell race cat. I've seen people saying get 2.5" and 2.75" or something like that? Not clued on about this tbh, so what sizes should i be looking at and what does this mean?

Also, the car has 2 cats and i would like a 100 cell race cat. Apparently if i do this, it may cause too much air flow which results in failing MOT? Can someone please confirm this? If this is true, will i be better off with a 200 cell sports cat?

Just to note, car is already running Stage 1 map but looking to do Stage 2 in a few months.

Help appreciated people. Have a good day! :happy:

Jay
 
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My advice to you would be to go for a 200cell sports cat as the difference performance wise is very small yet the chance of getting through an MOT with s 200cell is great.
 
Cheers for that Ben.

Little update: Going for a 200 cell sports cat as discussed with my exhaust guys today. Forgotten what they said about the exhaust measurements but i kind of know so help me out if you know what i'm mean please! lol

It's a turbo back system, 3" up until the box after the cat (silencer i think?) then 2.5" the rest of the way. Apparently it's pretty tight for a 3" the rest of the way and may hit any big bumps on road?

Appreciate your guidance on this people! As you can tell, i'm not that clued on technical things!

Thanks :)

Jay
 
C'mon you exhaust people, i know there's lots of you around here! :) If i can get an answer today and confirm what exactly i should do that'd be brilliant. Want to book the car in today for sometime soon (hopefully next week!).

Thanks people!
 
dont know how much help this is, but ive just had a custom system myself, but with a de-cat pipe and adapted the old cat to simply bolt back on when its mot time :) plus its a 2.5" system all the way from the downpipe as the guy said theres alot of bends that are awkward for a 3" pipe to go around!
 
How does your exhaust sound? I'm looking for a nice tone, nothing growly and silly loud!

Thanks

Anyone else have anything to share?
 
Thanks for the reply. Geting it done on Monday and decided what i'm going to do!

Turbo back system & 200 cell sports cat with 3" pipe going to the silencer. The rest from there wil be 2.5".

Don't want it to be very loud hence the 2.5" pipe. Will all this be okay?

Thanks!
 
The exhaust place should be able to advise best on what size pipe to go with, the only thing I would be worried about with a 3" pipe would be clearance issues as the last thing you want is for it to knock whilst driving.

Have a look on youtube for s3's with various exhaust ideas.
 
It's all good s-line ;)

3" pipe will be fine. Milltek, Blueflame, APR etc... provide these so it won't be a problem. Been searching around and heard no problems. Only thing i've been searching for on youtube is S3 exhaust sounds lol.

All is finalised now and booked for Monday! :D
 

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