I might be getting old but I'm fed up of the noise from my car. I have a sports cat 2.5inch centre H&S centre section with I think a H&S backbox (same as prodrive box). I already changed from a jap style as this was too loud but now I'm thinking of going back to std backbox to try and quieten it down.

Firstly, will this be any quieter?

Secondly, will it effect performance and by how much will it restrict the car?

The cars remapped by Jgm to about 275hp with the std td04.

Thanks.
Dave

 

I went from a cobra system to a standard Sti system on my classic.it was a lot quieter even with the decat.hope this helps

 

On my '99 classic PPP I have a straight through centre section with a standard Sti back box. It's quiet and subtle, but sounds lush, much nicer than the Prodrive backbox I had before. No effect on performance etc.

 

I really would like the car to be subtle. I don't like people hearing me before they see me. I do love the sound but hate it at the same time.

Might try the standard sti back box and see how I get on.

I would like to know if I would have any issue with the std turbo 2000 back box if anyone can help.

Thanks

 

I think the standard twin exit backbox is more restricted. There's a couple of classic STi backboxes on eBay:
http://www.ebay.co.uk/itm/SUBARU-IMP...item2348d27641

 

I got hold of an after market standard back box and I must say I'm converted

Don't feel embarrassed driving down the street now trying not to scare little old ladies with the noise from my car.

Surely loud exhausts will be the new dump valve.

If only I could get hold of a stainless back box that was as quiet as a standard one