Grahamwrx

Fitted a TSL 4” group N backbox along with the TSL de-resonated centre pipe for my UK 06STI and I’m well pleased with the sound, performance and looks !

Noise is slightly up on what I anticipated thinking that the 2 cats would keep the noise down, but it is substantially louder especially 4000 rpm plus !
Also I’m sure it feels quite a bit sharper on acceleration, I imagine 10 to 15bhp more, any guesses ?

The quality of finish and ease of assembly was spot on taking me about 90 minutes in total using 1 jack and an axle stand.

Overall I can highly recommend this combination for a shade over £300 delivered and believe me the burble is back!

Graham

fitzscoob

Doubt if a backbox gave that much, if anything at all. The bigger gains generally come from decatting the car completely.

Grahamwrx

yes but what would a backbox plus a straight through centre pipe give you in bhp?

[Davey]

You'ed probably see a very very slight increase in power, but no where near 10-15bhp!!

DarrenSTI

iTrader: (3)

I'd had the same on my car all be it a H&S, people thought about 2-5bhp at the most.

Beastie

iTrader: (2)

http://bbs.scoobynet.co.uk/showthrea...ti+dyno+result
Actually looks like an extra 34 bhp is obtainable with this mod.

JohnD

iTrader: (5)

But, he didn't de-cat the system - just removed the resonator. I would of thought removing one cat but retaining the resonator ( which is of absolute minimal restriction) might have been a better route, and would have controlled the noise output somewhat.
JohnD