Need some advice on my current exhaust, have recently bought a v8 sti which runs a straight through 3" system which is far too loud for my liking also worried about the fact that the decat downpipe will hinder me on the m.o.t,s so basically need some advice for quieter systems, I could go back to 2.5 system as don't think it's been mapped, but this will come at a probable big expense, been looking at the cobra track friendly system but still may have an issue with the downpipe,
As you can tell I'm at loggerheads pondering what to do so any advice would be much appreciated, cheers, matt

 

so its been de-catted but not remapped?......

 

i was in same situ
i had full 3 inch decat with the blitz nur spec ear bleeder r system
now 30 years ago i would have said it sounded great but age has mellowed me somewhat and can only say
Milltek 3 inch decat is just right nice burble but can still hear the stereo

 

That's right shreksta hasn't been remapped so need to make a positive decision really and go for it just really unsure and want to make the correct decision, will the power gains be substantial with a 3 over a 2.5 toyin with the later for the noise

 

2.5 3" is sapping torque without a remap

 

i would say that bore size doesnt make much difference to noise,you need to find out if your current system is resonated or not-look under the car so you can see the back box then follow the pipe there should be 1 or 2 boxes (1 cat and 1 silencer/resonator) then take it from there

a car with no resonator will be much louder than a car with a resonator,if your car hasnt then you need to source a system that has

either way when you have it done have a map done just to make sure,plenty of subaru's have gone bang because people have messed with them and not tweaked the map to suit

open source mapping is £350,your car will be quicker,smoother and most of all................SAFE

good luck