Dock0316

Hey Guys I went to my Local Speed shop and got my Vette Dyno, anyways the topic of Exhuast systems came up and they said they can make Full Stainless Steel Exhuast systems with your chose of 2.5 or 3 inch diam. aswell of the type of mufflers u want.. They said they will run the pipes as staright as possible without alot of bend and curves and also add a X-pipe for 1,100 installed what ya guys think?... Also last question if I were to go that route should I go 2.5 or 3?

TopSpeedc4vette

damn dude $1,100 for an exhaust that sounds a lil much to me but whatever floats your boat...haha and i think u should go for 2 1/2 inch

VetteNoob

you have an lt1 and i believe many here would say you should at least stay 2.75" or go 3" pipes on your exhaust system. i would say that if you are going to spend that kind of money to go with corsas, b&b, borlas, or power effects. they are all cheaper or cost similar to the setup you are considering. they are all also mandrel bend pipes where im not sure if the custom exhaust you want to do is. i think you can better spend your money on a quality pre-fabed system proven to fit and work with your car.

Mr Mojo

:iagree: :iagree:

_freakmonkeydogboy_

:withstupid: it would make much more sense to buy one that is proven to work than trusting some local shop that thinks theirs is better and charges more. Does this $1100 include the mufflers, or is that extra as well?

FELNGR8

First, what speed shop are you talking about? I'm in MD and might visit them myself sometime for the dyno.

I have an aftermarket set of chambered pipes, basically what is sold on MAD for C4 92-96. I didn't know MAD had them and found the manufacturer to buy direct. Point is, HERESY ALERT the guy advised me to go smaller than 2.5". I have the aluminized 2.25" inner diameter pipes and they flow very well. I can put my hand more than a foot behind the tips at idle and feel the power pulses strongly. This to me indicates that the velocity is kept up all the way through. Remember, 2.25" inner. If you don't have a big cube stroker you don't need something bigger in a true dual. The larger the pipe the less the velocity of the air.

It cost me $500.00. The same thing thing in T304 stainless is about $900.00. Dyno numbers are pending.

What I think is that for $1100 you should be getting titanium.


[Modified by 94lt1torchred, 11:01 PM 1/24/2003]


[Modified by 94lt1torchred, 11:02 PM 1/24/2003]

Dock0316

1,100 Bucks is everything with the X-pipe mandrel bend pipes and installed...

The thing is though if I were to go B&B that is 1,200 not including shipping nor installtion... Hmmm, this is very confusing not sure what to do, I mean I already got flowmasters I might just add longtubes, and thats the thing he said that longtubes wouldn't fit my vette since it was 2 low now is that true?..


The Speed shop is Called EIP tuning located in Westminster, MD

CORKVETTE1

if it is all 3 inch mandrell for $1100 out the door that is a honest price i had mufflex do a similar system for me in new jersey it cost me i think $750 but i supplied mufflers,hookups flanges,center equalizer and they supplied the mandrell pipe and did the labor all said in done with my parts it was $1000-$1100 so that is a honest price in my opinion a true dual 3 inch can support about 600 hp with ease :cheers:

FELNGR8

Westminster, hmmm, is Carroll County still excused from the dyno emissions test? If so then you can use long tubes without fear of the authorities. So the issue would be fitment and ground clearance. A shop that can do mandrel bends ought to be able to bend the headers to fit between the transmission and the frame. But I'm assuming a ZF6 like I have.

I have true dual (separated) pipes with no x-pipe and I have no problems with resonance. I know the x-pipes on the C5 give it a unique sound, but I can't figure out why everyone is crazy about installing them on a C4. Maybe I'm just a nostalgia freak and want to duplicate the sound of muscle in the 60s. The pipes I have do that very well. Frankly I would rather have my car sound like a 66 than a Z06.

But I seem to be alone in what I want from the exhaust sound.

VetNutJim

[quote]
If you don't have a big cube stroker you don't need something bigger in a true dual. The larger the pipe the less the velocity of the air.
[quote]

Bigger exhaust may not help but it sure won't hurt.

Think of it this way:
Use a 1/2 inch exhaust pipe. What will THAT do for velocity?
What will it do for volume?
Is the velocity closer related to piston speed or pipe diameter?

What would you rather have, a 1/2 inch exhaust pipe or a 6 inch exhaust pipe?

Just a few points to ponder.......

CORKVETTE1

6 1/2 inch :D :cheers:

VetteRacer282

$1100 seems a bit much.
Local shop is going to do mine for $800 installed.
3" Full Mandrel bent tubing, flanged at my headers. Another set of flanges for Cats or bypass pipes (system includes the bypass pipes), then back to the end of the car, with flanges and straight pipes out the back, as well as a set of flowmasters that will bolt to the flange.
So essentially two exhuast systems for $800 installed... $1100 seems steep...

BTW this is from a really good shop, does alot of custom turbo systems in town.

Oh yeah, he said it'd be only a couple more dollars (20-30) to do an X or H pipe

Matt


[Modified by VetteRacer282, 3:24 PM 1/25/2003]

C4kid94

Ya that price seems a little high, also i recomend 2.5" exhaust so you can keep some back pressure and not lose any tourque

FELNGR8

Comparing a 1/2 inch pipe to a 6 inch pipe is not a relevant discussion to any kind of reality. But I did some math on the sizes being discussed here, 2.25, 2.5, and 3 Inch.

Total exhaust pipe area . . . . . pipe diameter

18.85" cross section area . . . . 3 in
15.71 . . . " . . . . . . . . . . . . . 2.5 in
14.137 . . . " . . . . . . . . . . . . . 2.25 in

37.699 . . . " . . . . . . . . . . . . . 6 in

Just plain old Pi*D * 2 for the area of two pipes

So you see that a very small increase in pipe diameter is a very large increase in cross section.

Just to throw out a comparison of some (ir)relevance. Back in 92 or 93 (not sure) Dodge went from a single 2.5 in pipe to a 3 in pipe on the Cumins Turbo diesel P'up. They gained 50 HP from 250 to 300 in standard form. They have not increased the pipe diameter since, so the champion torque monster from Detroit even today is running a single 3 inch.

Be a little careful of going too large on a Vette with duals. Please remember, I said I picked up the phone to order 2.5 in pipes, and the manufacturer talked me into down-sizing to 2.25 instead. I'm very happy with what I got.


[Modified by 94lt1torchred, 11:29 PM 1/25/2003]


[Modified by 94lt1torchred, 11:33 PM 1/25/2003]

VetNutJim

91torch,

Congrats on your pi d squared calculations.
That backs up my point 110%.

The comparison between a 1/2 inch and a 6 inch exhuast was for illustration purposes and was meant to get those folks that think ANY back pressure in an exhaust system is a "good" thing to possibly reconsider the thinking.

Well, I take that back. The back pressure caused by a turbocharger may be a good thing. :)

On a NA engine if one could enable a vacumn in the exhaust to scavenge the exhaust gasses out, the AF mixture could be adjusted in a positive way to create more power.
Exhaust augmenters do this very thing.

If an engine NEEDS back pressure then the AF ratio is not set correctly or the
IE Overlap is too large.

For the same money the larger exhaust pipe diameter offers greater performance POTENTIAL than smaller.
As your calcualtions show, the cross sectional area increased substantially when the pipe diameter is increased. Of course there is a point of diminishing returns that is reached when the flow potential reaches the maximum flow the engine may generate at it's designed upper RPM.

DaveD

I never did understand that new math.......

18.85" cross section area . . . . 3 in
15.71 . . . " . . . . . . . . . . . . . 2.5 in
14.137 . . . " . . . . . . . . . . . . . 2.25 in

37.699 . . . " . . . . . . . . . . . . . 6 in

Just plain old Pi*D * 2 for the area of two pipes

If you use.....
Pi*D for circumference
...and...
Pi R squared for area
...it works better


;)

FELNGR8

Yeah, you're right, my math makes no sense. [Edit} I'm only 42 years out of high school and I've forgotten the basic formulas. I did the whole calculus sequence in my late thirties, and digging into those texts I found...nothing. So I asked my son and he knows its Pi r squared.

OK the areas of 2.25, 2.5, and 3.0 inch pipes. (who cares)

3.0........28.274 for one, 56 for duals
2.5........19.635 for one, 39.270 for duals
2.25.......15.904 for one, 31.8 for duals

It is not linear, and a small increase in diameter is a very large increase in cross-section area (and likely flow characteristics).

It's hell to get old and can't remember high school math. I hope I remember where my car is. And if I find it, I hope I can remember how to drive it.
[/edit]

* 2 was <times 2> for two (2) pipes. We're talking true duals here, not a y-pipe deal that actually restricts to one (1) 2.5 or 3 in pipe somewhere under the car. I was trying to compare total area provided to the engine. And only 4 cylinders are dumping into a pipe, but the x-pipe changes things later downstream.

Just for the record, I have been told that 2.5 " is enough for a 350-355. I was thinking 396 or 406 for a big stroker that can use 3 in. Any BBC is another discussion entirely.


[Modified by 94lt1torchred, 8:53 PM 1/27/2003]


[Modified by 94lt1torchred, 11:24 PM 1/27/2003]