As per title.... I have been reading around and it seems the 06/07 STI catback is the same as all other GD (2.0L) models and is close to 2.25" (see this thread on rexnet: http://www.rexnet.com.au/forum/index...23911&hl=2\.25). Anyone know for sure if the 06/07 is the same?

Apparently the Spec C catback is 2.5", can anyone confirm/deny this?

Anyone know anything in more detail about the internal structure/layout of these two mufflers?

Pretty sure the 06/07 ADM STI is 2.5" and I would be surprised if the Spec C is any different.

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No Subarus currently owned

the Spec C dump pipe is certainly different, but I was under the impression the catback would be the same

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MY93 Impreza GX 1.8L, 0hp, 0nm

2.5L gets bigger exhaust?

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MY93 Impreza GX 1.8L, 0hp, 0nm

If your talking about the STi cannon style exhausts then Spec C and S204 muffler are basically the same except materials and I can confirm the flange and piping diameter is 2.5.

However when Ramon cut open a Genome exhaust it had internal down
sizing so the only real way to find out would be cut it open.

Saying that the Spec C and S204/RA-R mufflers are not exactly restrictive
on making power and certainly flow better than a STD STi exhaust.

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221.7KW-ATW 498.5NM MMS ROLLER DYNO & BUILT BY STi NINJAS, BUILD #318/600

EBISU SUBARU, SHIBUYA-KU TOKYO

The 06/07 has a 2.5 inch mid pipe and a 2.25 inch diff back. (i bought naulis old diff back). Some Sti mufflers had a 2.5 inch diff back section, i have the 2.5 inch version on my xt, but i'm not sure what model it's off. I was thinking maybe a JDM Sti.
I think the spec c has a stainless version of the titanium s204 cannon muffler.
Here's one for sale.
http://www.rexnet.com.au/forum/index...owtopic=120752

I know thats why im asking the questions
What about noise I have heard genome catback, from about 2km away they are not exactly quiet, are these very similar to that or more like stock?

By the look of it, the spec C appears to be like a cannon ie. straight through design, correct or are they baffled design like the normal STI

I've had a Genome and the are quiet as a stock system when cruising
but mean and loud on WOT.

Why such a concern if it's baffled or straight through, the fact is
they flow and sound better than a stock STi exhaust?

If you want a super dooper free flowing muffler then go after market
or get a custom one made by Norm Butler.

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221.7KW-ATW 498.5NM MMS ROLLER DYNO & BUILT BY STi NINJAS, BUILD #318/600

EBISU SUBARU, SHIBUYA-KU TOKYO

or a varex.

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Long live the WRC

I was more just interested in the internal structure of the muffler.

Im basically after a super quiet setup but want as little restriction as possible, I know anything quiet will most likely be more restrictive (especially top end) but I can deal with small losses to keep the car quiet.

and I dont mean quiet as in compared to common aftermarket drain pipe exhuasts, I mean quiet as in factory exhuast quiet.