Dual exhaust on my 00 Legacy?

[subyguy522]

Ive been thinking about this for a while (20 minutes) and is it a waste of my time and money to try and fit a OEM dual exhaust from a 06-07 legacy onto my 00 legacy or could it happen?

[Reason]

I doubt it would fit. Not just the piping, but the 2nd muffler itself.

[OutbackGT]

I don't think it would even look good without the cutouts in the rear bumper for the pipes, anyway.

[Huffer]

You can make rear cutouts - and you can have new hangers welded onto the frame.

I think it would look hot. Performance-wise, unsure, you'd need a decent V-split (no T-junction).

[Reason]

On the 2nd gen there is a "Evaporative emissions canister" where you would put the 2nd muffler. I'm not sure the layout on the BE's.

[rougeben83]

On the 2nd gen there is a "Evaporative emissions canister" where you would put the 2nd muffler. I'm not sure the layout on the BE's.

It's there too. that's the big black plastic box right?

Yeah, I wouldn't be messing with that.

Unless of course you want to go real ghetto and use a mid muffler somewhere after the rear diff but before the sparetire well, and run two straight pipes to each end of the car.

[Wiscon_Mark]

Or just run straightpipes with resonators :lol:

[badbasser98]

Unless of course you want to go real ghetto and use a mid muffler somewhere after the rear diff but before the spare tire well, and run two straight pipes to each end of the car.
Without getting under the car, I can't say for sure. But this method seems to be the only way you could go dual, or find a VERY low profile muffler like the Spintec's or something. Between the gas tank and the spare tire well I think you are going to have trouble running a pipe to the right side of the car with out it looking like ass and losing clearance.

[02LGT]

i think if u get a dual exhaust u will lose power. i know s2k's with dual exhaust change their setup to single tip to increase performance. also it will look ricer haha juss my opinion...but its unique.

[rougeben83]

Well note, that what most people talk about nowadays with "dual exhaust" is a quasi dual with a single pipe running to a Y and splitting to two mufflers; the real dual setup would be like the old school musclecar V8's with two pipes running from each bank of cylinders.

And yes, you would loose some backpressure, but more so, you're adding weight for looks.

Running a bigger diameter pipe to one muffler will make a more effective mod than going dual IMO.

[subyguy522]

Thanks for the tips... it doesn't seem worth it with the power loss and all things considered. If it could be done though, i think it would look nice if done correctly and cleanly. Thanks again.

[Wiscon_Mark]

backpressure does not = power.

[OutbackGT]

backpressure does not = power.

True, but not having enough back pressure can be almost as bad as having too much. Don't ask me how, though.

[Wiscon_Mark]

that's the common misconception - that backpressure is on the super small tube side - that's just choking the fluid pressure. Backpressure is actually created when you have too large of tubing and the exhaust gasses cool off inside the piping, slowing things down. You want to eliminate backpressure as much as you can, it's not a balance.

Keeping heat in the exhaust system is what creates power - or at least conserves it.

[rougeben83]

+1. Heat in the pipes, or more accurately exhaust velocity (gas velocity is a product of how hot it is), and least amount of turbulence FTW.

[OutbackGT]

that's the common misconception - that backpressure is on the super small tube side - that's just choking the fluid pressure. Backpressure is actually created when you have too large of tubing and the exhaust gasses cool off inside the piping, slowing things down. You want to eliminate backpressure as much as you can, it's not a balance.

Keeping heat in the exhaust system is what creates power - or at least conserves it.

Interesting. But then... why aren't people running like .25" diameter pipes? There must be some sort of balance.

[badbasser98]

its all about maximizing flow... too small and its deminished, too large and its hurt as well....

[rougeben83]

Right, too small and you're restricting flow, but go too high and the gases spend too much time in the pipes, loosing heat (loosing energy, loosing exhaust velocity), so that's what the perceived "loss in backpressure" pops up.

[Wiscon_Mark]

Right - I did mention that in my last post, although not terribly clearly. So what most people percieve as a loss in backpressure is actually an increase in it.

[blackgtbeauty]

With that setup why would you loose backpressure? the new 2.5i's have the same setup on a engine of the same displacement and very similar power output?

[rougeben83]

With that setup why would you loose backpressure? the new 2.5i's have the same setup on a engine of the same displacement and very similar power output?

Note I said *slight*. Muffler choice, resonator/unresonated, etc. also come into play. Although it's pretty uncommon to have any perfomance gains by going with a quasi-dual setup in most cars to be honest, it's more of a cosmetic thing.

If you go with the mid-muffler setup right behind the rear diff, you'll have two long pipes that exit after it, and that would actually add more restriction, as the exhaust gases are allowed more time to cool, thus "increasing backpressure".

[SubiFlow]

With a little research on the internet you can find several sites that explain exhaust systems, i would recomend Flowmaster Mufflers website. some cars could improve with better headers, mufflers and cats.