STi exhaust on WRX

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Dec 31, 2003 | 07:37 AM

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STi exhaust on WRX

Has anyone seen any improvement using the new STi muffler with an aftermarket DP versus aftermarket DP with stock WRX muffler. I like using factory parts whenever possible, and they can be had pretty cheap. I'm looking for someone who has dynoed this setup.

Dec 31, 2003 | 12:25 PM

tk1971

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From: So Cal

Car Info: 2002 WRX

I've got an STI muffler along with my one cat (mid pipe) exhaust and during the Great EZ Street Dyno Debacle (and after applying some math in excel for comparison to other dyno numbers). It showed my VS2 setup (with my own one-cat exhaust setup with the STI muffler) gave about 20 WHP less than Vishnu's dyno numbers of the same setup with the catless exhaust and their special downpipe.

Is this what you were looking for?

tk

Dec 31, 2003 | 02:23 PM

Kevin M

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I like to think of the STi exhaust in these terms- Stock STis put about 215 whp on the Vishnu dyno. STis with a good 3" turboback put down about 245-250.

Dec 31, 2003 | 03:00 PM

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Doesn't really help unless done on the same dyno.

Dec 31, 2003 | 03:50 PM

tk1971

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From: So Cal

Car Info: 2002 WRX

Sorry, but I'm not writing a "mod" article, nor plan to be in one anytime soon. I just wanted a baseline after all my "final" mods.

But good luck to you. BanSUVS reply sounds more like what you are looking for.

tk

Dec 31, 2003 | 06:15 PM

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Quote:

Originally posted by BAN SUVS
I like to think of the STi exhaust in these terms- Stock STis put about 215 whp on the Vishnu dyno. STis with a good 3" turboback put down about 245-250.

I'm trying to figure out how much I would be gaining or lossing with using the stock STi axleback with Uppipe, Perrin catted DP, and I now am using the WRX cat back. Will the STi muffler make anymore power? How much am I lossing compared to a 3" catback?

Jan 1, 2004 | 09:11 PM

Kevin M

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Quote:

Originally posted by Silver arrow
Doesn't really help unless done on the same dyno.

Those are baseline and 3" turboback numbers for an STi on the Vishnu dyno, no tuning.

Jan 1, 2004 | 09:12 PM

Kevin M

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Quote:

Originally posted by Silver arrow
I'm trying to figure out how much I would be gaining or lossing with using the stock STi axleback with Uppipe, Perrin catted DP, and I now am using the WRX cat back. Will the STi muffler make anymore power? How much am I lossing compared to a 3" catback?

The STi catback section isn't all that much better than the WRX. The piping is slightly larger, bt the muffler design is about the same. If you have a 3" downpipe, then you would see big gains from a 3" catback over the sTi section. Probably 10-15 hp.