Dual pipes?

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glassjaw
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Dual pipes?

Post by glassjaw »

I know I am making many new posts regarding upgrades... but my new job is going to start paying a lot better soon, and I want my Subaru to run better too!

Would running two pipes, one from each head offer much of a performance increase? I assume it would sound totally kickass from behind, with some dual chamber mufflers or less.

I could probably have a local pipe bender do it for not much more than a few hundred $$$, including the mufflers, and dual "cats :wink: ".
1998 Impreza L coupe...

Past Subies... 1999 Legacy L AWD, 1994 AWD L, 1992 AWD L, 1990 FWD L, 1990 AWD L. Pretty much all I drive.
evolutionmovement
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Post by evolutionmovement »

Difficult packaging with the second muffler unless you have them both come out the same side.

Steve
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glassjaw
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Post by glassjaw »

They would have to come out on each side for the sound :).

I will look into it a bit more, just wanted to see if anybody had personal experience with this.
1998 Impreza L coupe...

Past Subies... 1999 Legacy L AWD, 1994 AWD L, 1992 AWD L, 1990 FWD L, 1990 AWD L. Pretty much all I drive.
Legacy777
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Post by Legacy777 »

You'd have to make the piping be a bit smaller, or you're going to lose too much velocity, and it's just not going to yield any gains.

I had a buddy in memphis who had true dual exhaust on his SVX. It was a little raspier, but sounded pretty good.
Josh

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BAC5.2
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Post by BAC5.2 »

Josh has got it!

You'd have to run 1" pipes from each side (and have a connecting bit to make sure flow is even).

Probably would sound pretty cool, but a straight pipe will sound pretty cool too :)
2009 Outback 2.5XT. 5MT. Satin White Pearl.
2009 Impreza 2.5i Premium. Blue.

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evolutionmovement
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Post by evolutionmovement »

Yeah, you'll lose scavenging properties on a large exhaust with only 2 cylinders.

Steve
Midnight in a Perfect World on Amazon or order anywhere. The first book in a quartet chronicling the rise of a man from angry criminal to philanthropist. Midnight... is a distopic noirish novel featuring 'Duchess', a modified 1990 Subaru Legacy wagon.
white_n_slow
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Post by white_n_slow »

it may be helpful to use a dual-pipe muffler... one muffler with two cores running through it. I'm not very familiar with the underside of legacies, but that would probably be the easiest way to package a dual exhaust.

there are a few companies that sell them... magnaflow, burns stainless, probably some others too.
non legacy owner.
93Leg-c
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Post by 93Leg-c »

If you want your Suby to run better, don't go with two separate pipes. You're going to regret it. When I was into air-cooled VW Bugs, the 4-into-1 header setup was the best. All those that went to the 2-into-2 setups (like dunebuggies) regretted it. It made their Bugs run worse, noticeably worse. Less power, less torque, less gas mileage, but MORE frustration!
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