cat back exhaust 2.5" vs. 3"
Thread Starter
Heel & Toe
Joined: Apr 2013
Posts: 20
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cat back exhaust 2.5" vs. 3"
I have a '92 Vette all original equip, stock, LT1, 23k miles, 6 speed manual trans. I have been looking at cat back exhaust systems. Some are offered in 2.5" and some are offered in 3". Please explain the following:
- Is there a difference in sound between the two sizes?
- I have a 2.5" system, can I use a 3" system?
- Is there a difference in performance between the two sizes (good or bad)?
- Will a cat back exhaust change require any sensor changes or computer changes?
- Is there a difference in sound between the two sizes?
- I have a 2.5" system, can I use a 3" system?
- Is there a difference in performance between the two sizes (good or bad)?
- Will a cat back exhaust change require any sensor changes or computer changes?
Last edited by dennisd1251; May 11, 2013 at 01:06 PM.
Team Owner
Joined: Oct 2004
Posts: 81,241
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From: altered state
St. Jude Donor '05
Youwont get any gain on a 3" plus it will be louder and drone
Edit- look at the size of the collector on the LTx manifold. Wont get any more air through there/size no matter how big the pipes are behind that.
Edit- look at the size of the collector on the LTx manifold. Wont get any more air through there/size no matter how big the pipes are behind that.
Last edited by cv67; May 12, 2013 at 12:00 AM.
Since you essentially have dual 2 1/2" pipes your exhaust flow is good to ~1000cmf, enough to support >400chp.
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
IN THEORY....
You want the pipe size to maintain constant to slightly decreased diameter -- as gases move to the rear of the car.
Theory says this keeps escape velocity up and helps with scavenging (also so lift-off is possible).
IN THEORY....
2.5" is my vote too.
You want the pipe size to maintain constant to slightly decreased diameter -- as gases move to the rear of the car.
Theory says this keeps escape velocity up and helps with scavenging (also so lift-off is possible).
IN THEORY....
2.5" is my vote too.
