Single or Dual Exhuast?

[sorrowfulkiller]

Once I move I'll finally start to mod my car, but I haven't decided on Single or Dual exhaust yet. Near the end of the summer I'll be buying a turbo kit (they sell grand am ones on ebay) so I want to go with a 3 inch catback for now and once I get the turbo put on I'll change out the headers, downpipe and cat.

What would sound better for a 3 inch turbo setup, Single or Dual?

[PFC2]

single

[jackal2000]

single

[sorrowfulkiller]

Alright, thanks...

btw with the 3 inch catback before I get the turbo, will that give me quite a bit less power in the lower rpm's or will it affect it very little?

[jackal2000]

Originally Posted by sorrowfulkiller

Alright, thanks...

btw with the 3 inch catback before I get the turbo, will that give me quite a bit less power in the lower rpm's or will it affect it very little?

umm yea. hp will drop and torque will be decimated.

[billytheman1188]

why a 3in exhaust???? thats what my step dad has on his 8 CYLINDER truck, why not just go with 2.5in??? people on here told me to go with 2.25 or 2.5, no bigger than that.

[BlackJack]

billy, the difference is in turbo or N/A.

with turbo, you need max flow to get out of the engine, fast as possible.
with N/A, you need some backpressure to retain low-end torque.

so.....with N/A, 2.5"
with turbo, 3"

[billytheman1188]

Originally Posted by BlackJack

billy, the difference is in turbo or N/A.

with turbo, you need max flow to get out of the engine, fast as possible.
with N/A, you need some backpressure to retain low-end torque.

so.....with N/A, 2.5"
with turbo, 3"

ahh ok, SHIT, well i guess i wont get a turbo in the future, i mean that wasnt my number one thing i wanted to get just yet, but i guess i will just do headers, high flow cat, DHP.... thanks for the info though

[BlackJack]

if you're forking out for headers, you're going to waste alot of money going to turbo anyway, because it's very different, and they're not interchangeable.

[billytheman1188]

Originally Posted by BlackJack

if you're forking out for headers, you're going to waste alot of money going to turbo anyway, because it's very different, and they're not interchangeable.

oh alright, its not even a big deal if i dont get a turbo anyways, i mean i would love to get one, but there arent ANY tracks around here, and i will be happy with headers, thats the most expensive performance mod im probably going to do....

[sorrowfulkiller]

Alright, So in other words do exhuast roughly the same time as the turbo?

Hey blackjack, did you get a custom downpipe made or what?

[BlackJack]

yeah, here you can see where I was test-fitting it before I added coating and header wrap. germ made the downpipe and just tacked it together in case I needed to readjust, then I had it final welded here locally.

This shows the position of the turbo:


This shows where the downpipe comes out the turbine housing and loops behind the engine just over the rear header, and then down the firewall:

[alerored04]

i still cant beleive how gorgeous those things are and cant wait until i can afford to have jeremy start mine.

[BlackJack]

oh, you will probably like this then......

http://www.aleromod.com/forums/showt...841#post253841

[Spilner521]

Originally Posted by BlackJack

billy, the difference is in turbo or N/A.

with turbo, you need max flow to get out of the engine, fast as possible.
with N/A, you need some backpressure to retain low-end torque.

so.....with N/A, 2.5"
with turbo, 3"

Not going to really change anything, just tweak your post a little to be more accurate.

With turbo, you need max flow to get exhaust backpressure off the turbine to spool as quick as possible.
With N/A, you need to maintain exhaust velocity to retain low-end torque. Backpressure is bad.

To answer sorrowfulkiller's original question, a single exit 3" exhaust will flow the best. A dual exit system will not flow any better, but will not flow worse either, so you will not gain or lose power. Duals are pretty much just for looks. You will gain power with just the 3" cat-back mostly in the upper rpm's and shift the low end torque higher up in the rpm range.

[BlackJack]

yeah, backpressure is kind of a bad generic term, but yeah, basically maintaining flow velocity at the right diameter helps "pull" exhaust out.

[Spilner521]

Originally Posted by BlackJack

yeah, backpressure is kind of a bad generic term, but yeah, basically maintaining flow velocity at the right diameter helps "pull" exhaust out.

Yes.

And on a side note BlackJack, I do really like your setup. Almost makes me want to drop in a built 3400 . And since we're talking about exhausts, I'm just curious, what kind of setup do you run (pipe size, cat. muffler, etc.)?

[BlackJack]

Thanks bro.

3" straight downpipe that stops right before the rear crossmember. No cat, no EGR, no muffler.

and the WG is atmospheric dump.

[Spilner521]

Originally Posted by BlackJack

Thanks bro.

3" straight downpipe that stops right before the rear crossmember. No cat, no EGR, no muffler.

and the WG is atmospheric dump.

Damn...talk about ultra flow. It's gotta be a little loud though.

[BlackJack]

it's loud, but not as bad as you would think. it's about like having a large glasspack or 50 series flowmaster, with no high tones.

That turbo actually cuts up the soundwaves coming out, which pretty much destroys high tones. meh....or something like that