Quiet 3" exhausts?
 

Looking for recommendations on a 3" exhaust system that is track friendly for my 420bhp Blob STI

I currently have a 3" cobra sport system, and the centre pipe does have a resonator but the system is just too darn loud for my old ears (and my neighbours) so I'm looking to change.

I've seen that Cobra do a track friendly cat back, but at £500+ for the 2 sections it's not really budget friendly for me. Someone did suggest having an extra silencer fitted to the centre section on my current system but I believe its the backbox that is generating most of the noise level.

I'm fimiliar with the Milltek brand, but all the cat back systems i've seen are 2.75" vs the 3" I currently have. Would 1/4" make much difference at my power level (420 @ 1.5 bar)?

Would be keen to know if/what other people are running that pass track noise limits, and if anyone is interested in a swap for something louder I'd be keen.

Many thanks

Jetex/ revolution system is good for track days. Think it's around 370-400 new. Before I got this I had the cobra track day system, you have to be careful as some come with a 2.5" end to fit a standard down pipe.

I did hear about Jetex but couldnt seem to find a supplier or any pricing. Dont suppose you have a link or supplier name?

a mid section silencer is a cheaper option and will reduce noise by about 20 per cent , you could always swap it in and out depending on how much noise you want , it’s a fair clump of money to do a new system when you could tone it down at less cost

that was my 1st initial thought mate, my only concern was that with it already being a resonated centre I get the feeling its the backbox generating the noise. As you say, its a cheaper alternative so I may see if I can find somewhere that can add a mid-silencer and go from there.

I’ve a HKS Hi-power Silent on my Type Ra, seems relatively quiet compared to most.

I have a custom H&S down pipe, custom centre straight pipe with NO silencer and a milltek back box and it was 86db at 4krpm iirc.
Milltek box does make a difference.

I second the revolution/jatex system, I've seen some good power from them too, I would go for that if I didn't have current system

I have the same exhaust on my Evo, was static noise tested at 86db

I run the Cobra track friendly system and it makes SO much difference. You should be able to sell the rest of your Cobra system on here or ebay.

We're also a Cobra reseller, so I should be able to get you a good price, if that helps.

I have an RCM track friendly turbo back system for sale that was on my 500bhp sti

could you pm me some details please :thumb:

I have a 3" power flow cat back system. Not to loud and fine on drives. Although my next door neighbour did complain a few times about noise if I came in late at night. You can't win.

i would still suggest as above adding a mid silencer , it will reduce the noise a lot and most exhaust places won’t charge much to do it , i went louder on all of my cars the mid section does have quiet a large effect , you can buy back boxes with electronic flaps in them or get one welded in the system but motor life is questionable

I've the 3" turbo back Cobra track day exhaust on my hawkeye. It has two resonator boxes on the midsection and is relatively quiet but does have a lot of base. Cabin noise is fine.

I've even had a couple of people on our estate come over and tell me how nice it sounds, ten times better than the couple of Golf Rs a few doors down.

You may be best going to a breaker with a few options in and try swapping sections for a couple of hours. I think you need to stick with a full 3" for your bhp though regardless of cat or not.

this is what is on mine atm I think. The base is so bad it rattles my front doo lol. Just ordered a cobra SB05-Z. Resonated catback. Will that be louder?