Exhaust size

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Sep 7, 2001 | 08:53 AM

Bradley3

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From: Millington mI

Exhaust size

the guy I bought my car for SOME reason decided to modify his exhaust by running 3.5 inch pipes (or so he says) w/ no mufflers.

the car SOUNDS great.... but I can't help but think I might be losing some performence.

- 1st of all do they even make pipe that big? or do you think he meant 2.5 inch?

- am I gaining or losing anything w/ this mod? (besides sound)

- should I leave it how it is or spend the $75 or so to have the stock 2.25 put back on at my local muffler shop? (i'm mainly concearned w/ performence)

Sep 7, 2001 | 09:18 AM

mackeyred96

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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey

Cruise-In VI Veteran

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Re: Exhaust size (Bradley3)

Welcome to the forum.
What year car?

Sep 7, 2001 | 09:27 AM

Bradley3

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From: Millington mI

Re: Exhaust size (Bradley3)

it's a 92 automatic :cool:

Sep 7, 2001 | 10:21 AM

lcvette

Melting Slicks

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From: Wilmington NC

Re: Exhaust size (Bradley3)

Bradley welcome to the forum,
i run 3" exhaust on my 95, if i were you i would check to ensure if the cats are still there and if they are still functional. as long as the cats are on the car, im sure you still making enough back pressure for th motor to run as Gm designed it. the bigger pipes at most might even help on the top end of the rpm range. this would bemy view on the matter others may have more infor for you!! welcome again and enjoy!

chris :cheers:

Sep 7, 2001 | 02:38 PM

GlockLT4

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From: Dallas TX

Re: Exhaust size (Bradley3)

3.5" pipes should be used on a car with around 600+ HP, I don't think 3.5 was a wise dicision by previous owner. Stock on mine is 2.75, and I might possibly go up to 3", but for now, making 350flyhp, I definitely don't NEED bigger exhaust.

[Modified by Glock'94, 12:38 PM 9/7/2001]

Sep 7, 2001 | 05:00 PM

Bradley33

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From: Millington Mi

Re: Exhaust size (Bradley3)

The exhaust was redone from the cats back... so they are still functional

I know 3.5 inch isn't optimal... but if I have enough back pressure right now to allow the engine to run without a performence hit I think I'm just going to leave it.... for the time being.

The exhaust does taper back to stock size... because he welded the stock tips back on.

I was just making sure that I wasn't losing out on any performence.

Thanks

Sep 7, 2001 | 05:51 PM

KLLRVET

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Joined: Dec 2000

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From: Cape Coral fl

Re: Exhaust size (Bradley33)

Have you measured it to be sure he was correct? Sounds like all you got was a muffler eliminator kit.
Tony

Sep 7, 2001 | 06:34 PM

Nomar116

Burning Brakes

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From: Lemoore CA

Re: Exhaust size (KLLRVET)

Exhaust is like water running through a series of pipes. Just like anything in life, your only as strong as your weakest link. Stock exhaust pipes or tips or whatever it is, defeats the larger diameter exhaust leading to that point.... Now that doesnt mean its not better, many aftermarket pipes are going to still be able to flow more smoothly, but larger diameter will do little to benefit unless done the whole way through. In other words, with the stock cat and front Y dont think twice about the exhaust. You could even change the muffler tips making them larger with no harm done, and probably gains. None the less, on that stock vette, with the rest of the stock exhaust system, I would just worry about sound resonance.
My $.02
Paul