Any gain for open headers?
Thread Starter
Team Owner
Joined: Mar 2000
Posts: 83,383
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From: Boston, MA
Any gain for open headers?
I know I've asked this before, but will agian.
I am thinking of modifying my catback so that it can be dropped at the front of the rear y-pipe approximately 4.5" with little effort. This would allow me to run the exahust completely open. (headers, and 3" pipe in place of the cat).
Would there be a significant gain to make it worth the effort? This would be strictly for Sat/Sun at the track when you can run open exhaust. How much (if any) risk of burning up my exhaust valves would there be?
I am thinking of modifying my catback so that it can be dropped at the front of the rear y-pipe approximately 4.5" with little effort. This would allow me to run the exahust completely open. (headers, and 3" pipe in place of the cat).
Would there be a significant gain to make it worth the effort? This would be strictly for Sat/Sun at the track when you can run open exhaust. How much (if any) risk of burning up my exhaust valves would there be?
Team Owner
Joined: Apr 2000
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From: CT
Re: Any gain for open headers? (scorp508)
JMHO
That is a thing of the past. Todays systems are very efficient. I don't think you'll gain that much. Unless you're looking for every little hundredth...or you like the loud noise! :) Corked up wouldn't be a bad thing.
JD
That is a thing of the past. Todays systems are very efficient. I don't think you'll gain that much. Unless you're looking for every little hundredth...or you like the loud noise! :) Corked up wouldn't be a bad thing.
JD
Melting Slicks
Joined: May 2001
Posts: 2,143
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From: San Diego CA
Re: Any gain for open headers? (scorp508)
I don't think there is any danger of burning up your exhaust valves. There seems to be a bunch of members here that have removed or gutted their cats. I don't recall any "SHOOT, I burned up my exhaust valves after gutting my cats" posts.
A friend with a 92 Camaro (I don't recall which engine), and an exhaust setup as you described, dyno'd his car several years ago. He said he only saw about 5peak HP difference and no change in torque without the cats.
He ran one auto-x with it and got DQ'd because he exceeded the local 93db sound limit.
He claimed it's only good for making more noise.
A friend with a 92 Camaro (I don't recall which engine), and an exhaust setup as you described, dyno'd his car several years ago. He said he only saw about 5peak HP difference and no change in torque without the cats.
He ran one auto-x with it and got DQ'd because he exceeded the local 93db sound limit.
He claimed it's only good for making more noise.
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Re: Any gain for open headers? (scorp508)
You may see a small gain but only if you tune for open headers. You can't tune for both at the same time.
Melting Slicks
Joined: Apr 2000
Posts: 2,793
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From: Elizabeth City, NC
Re: Any gain for open headers? (mackeyred96)
There may be a gain in peak HP, but across the board you will suffer. You will be lacking TQ. And like Mackey said, it must be tuned for that particular setup to be effective.
Thread Starter
Team Owner
Joined: Mar 2000
Posts: 83,383
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From: Boston, MA
Pretty much what I expected. So unless I had a 2nd chip tuned for them, it's pointless. A little less torque MIGHT be worth it if it picks up on the top end. I'm probably going to have too much down low to begin with. :) I'll play it by ear once she's up and running around.
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