Exhaust Header Upgrade
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Exhaust Header Upgrade
I'm running the stock 1985 exhaust "shorty" exhaust manifolds and want to upgrade to a better setup. Not a long tube header but something that resembles the stock ones but with a bigger diameter tube(s). Hopefully with AIR fittings on too. Needs to pass smog.
Am I asking for too much? TIA (car is 1985)
Am I asking for too much? TIA (car is 1985)
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
If you're asking for any performance gains, then yeah, you're asking too much.
I removed my heat shields and painted mine. I'm gonna go long tubes and do the biannual swap, or just leave it alone.
I think they'res a worthwhile gain by porting them, and grinding down the air tubes... the ports are welded on the inside and look like ****.
I removed my heat shields and painted mine. I'm gonna go long tubes and do the biannual swap, or just leave it alone.
I think they'res a worthwhile gain by porting them, and grinding down the air tubes... the ports are welded on the inside and look like ****.
Large Impressive Member
Joined: Jul 2003
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Technically you should be able to get away with longtubes in CA. on the '84-'85 cars since they had no pre-cats. But in practice, this does not seem to be the case due to overzealous smog *****. There are a number of shorties available with A.I.R. hook-ups.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Yeah, we could have carb legal long tubes, but no company has yet to pursue getting the EO number, surprisingly. I guess they didn't see it as worthwhile. After all, Corvettes are for old fogeys.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
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From: Santa Maria CA
Originally Posted by Corvette Kid NC
Technically you should be able to get away with longtubes in CA. on the '84-'85 cars since they had no pre-cats. But in practice, this does not seem to be the case due to overzealous smog *****. There are a number of shorties available with A.I.R. hook-ups.
Large Impressive Member
Joined: Jul 2003
Posts: 65,811
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by 86PACER
It's more that long tubes have no C.A.R.B or E.O number. Most of these places dont' even know what year C4's had pre-cats and which did not. I use a front y-pipe for the bi-annual swap with no pre-cats and they never say anything. The smaller shops see lots of cars and very few if any C4's to know.
It's stupid really. Headers aid in the efficiency of an engine so in effect, properly tuned, it will emit fewer emissions because it's using less fuel to do the same work. Stupid f'n bureaucrats. 
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
You got that right. 
I though the bottom line was just what came out your tailpipes, not what C.A.R.B or E.O. numbers products have. At least that's what I think the bottom line should be. 
I though the bottom line was just what came out your tailpipes, not what C.A.R.B or E.O. numbers products have. At least that's what I think the bottom line should be.
Last edited by 86PACER; Dec 22, 2005 at 11:28 PM.
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Originally Posted by 86PACER
You got that right. I though the bottom line was just what came out your tailpipes, not what C.A.R.B or E.O. numbers products have. At least that's what I think the bottom line should be.
I though the bottom line was just what came out your tailpipes, not what C.A.R.B or E.O. numbers products have. At least that's what I think the bottom line should be. 
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Race Director
Joined: Jan 2005
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From: Slidell Louisiana
Originally Posted by Corvette Kid NC
Fortunately I live in a free country instead of CA. It's stupid really. Headers aid in the efficiency of an engine so in effect, properly tuned, it will emit fewer emissions because it's using less fuel to do the same work. Stupid f'n bureaucrats.
It's stupid really. Headers aid in the efficiency of an engine so in effect, properly tuned, it will emit fewer emissions because it's using less fuel to do the same work. Stupid f'n bureaucrats. 
Chris that looks like something I would post. Good job!!!!
Mike
Instructor
Joined: Dec 2005
Posts: 197
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From: Woodland California
Ca smog
I guess I'm lucky. My smog guy is a drag racer. His attitude is that he cant know all cars. If it it suposed to have precats, and you weld in pre cats after the long tube headers, and have cats, it meets Cailfornia state requirements. If it passes the snif test, it passes. E-mail me, jowensmd@sbcglobal.net if you want his address.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
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From: Dublin CA
I have looked extensively and can tell you that there is not a smog legal header for a 1985 that is accepted by the State of California. Can't find a long or short tube version witha CARB number. The best that you can do (and be legal) is to go to a 2-1/2" front "Y", high flow cat, 2-1/2 rear "Y" and a good high flow after market muffler.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I know for a fact there are several carb eo numbers for shorty headers. Whether or not any of them are still produced, I don't know. One that comes to mine is JBA here in San Diego.
