I have a 97 Classic with a 2.5" Miltek system.

It has a single cat in the hi-flow down pipe and a straight though centre section.

I'm finding it a bit loud for motorway use and thats mainly the miles I do.

Anyone got experince of the system with a centre section with integrated muffler ? Do you loose power ? Is it noticably quieter ?

Anyone got one they's consider swapping ?

Cheers

 

Mine was on a Forester STI.

I had the straight-through centre section until the 1000-mile service, then it was swapped for the resonator centre section.

Externally the noise was a lot quieter, especially the 'agressive' noise under load. The internal noise was reduced but not as much, there was one particular engine speed where it droned through the cabin (around 3000 rpm, which is motorway cruising speed). That's probably worse on the Forester because the rear floor area is open to the cabin.

No power loss noticed with the resonator.

For a time I tried the OEM Forester STi back-box and the exhaust was almost inaudible, so I'd say it is the Milltek BB that creates the noise.

You could try some soundproofing of the floor of the boot, and make sure the folding seats (if yours fold) are not leaving a gap so more sound comes through.

 

Ricardo

Thanks very much, this Scoobynet really does come up trumps sometimes.

I don't care about the external noise so much and if adding a resonator centre section doesn't help that much internally I'll think again. Like you say, sound proofing the boot has got to be a good start.

Mind you, I'd still be interested from anyone with an Impreza on this thread.

Perhaps its the hi flow cat that lets more sound out than the standard unit ?

Anyone with de cat / hi flow cat internal noise experience? - Think it'll have to be a new thread for takers on this question.

Thanks again though