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headers

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GigiAvanti

Guest
I want to install headers on my 1976 L48 Corvette in order to improve horsepower. I am considering buying Hooker headers, but was told these headers are not smog legal. If I install these headers, will I have a problem getting the car smogged (I live in CA), and if so, are there any other headers you would recommend?

Thanks.
Gigi
 

mmvette80

Well-known member
Joined
May 12, 2002
Messages
273
Location
Central NY
Im in the same boat as you, only 3000 miles away. I have been searching also. What I have gotten is that there are smog leagal headers. Call headman direct and talk to them. They have the A.I.R. Tubes on them. Thats all fine and dandy but I dont even have the Smog pump on my car. I havent had mine inspected since Jan 2001.
 
R

rpounds

Guest
I have been searching for a very long time for Kalifornia legal headers for my '75. I am of the humble opinion that they do not exist . . . at least not for my year/make/model. The problem is the EFE (the gizmo that opens and closes the heat riser with vacuum). There is no way to incorporate that into a header system. You will undoubtedly have the same problem with your '76. Unless they change the laws, I only have two more smog checks to go through and then I'll be in the clear. Then headers HERE I COME!!

Anything that is installed on a Kalifornia pollution controlled vehicle has to have a C.A.R.B. ((K)California Air Resources Board) certification in order for it to be legal. BUMMER . . .
 
R

rpounds

Guest
Tom,

Those still will not fly in California. They have provision for the AIR tubes, but they still can't get around the vacuum operated heat riser (EFE).

Ron
 
1

1DOWN6TOGO

Guest
what are the laws for antique or classic vehicles in cali?
i have mine registered as antique in TX because it's 25 years old, that is the age of "maturity" i guess. and for a vehicle registered as antique emissions regulations basically fly out the window.
do you know of any loopholes like that out there?
 
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rpounds

Guest
There are no loopholes here in California. Even farm equipment is registered if you can believe that.

A car has to be 1973 model or older in order to be disqualified from testing. However, once we reach 2003, the law is supposed to change to a rolling 30 year exemption, so after 2003 when your car turns 30, no more testing.
 

WhalePirot

Well-known member
Joined
May 9, 2002
Messages
2,942
Location
SoCA
Corvette
1984 White Z-51/ZF6-40/Shinoda body
CA legal for (C4)

For my '84 I used headers by TRACO which were set up to connect to my AIR systrem. The first attempt to smog resulted in a recommendation (smog guys were more accomodating back then) to add a small, fabricated pipe to pass heat from the header to the air cleaner intake. We used a short (about 2") pipe, about 1 1/2" in diameter,, welded a tang on it and attached it to either cylender 3 or 5 with a hose clamp. It was enough to satisfy the requirement.

I'd also strongly recommend ceramic coating or wrapping them to eliminate underhood heat and increase the scavenge effect. Same also gets more heat to the CAT, which needs it.

Maybe this C-4 idea will stir the imagination of the C-3ers.

:w
 
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rpounds

Guest
WhalePirot,

What you are referring to is the thermostatically controlled air cleaner heater duct. I'm not sure about '76 vettes, but '75s did not have this feature. The heat riser that I am talking about is between the right hand exhaust manifold and the exhaust head pipe. Same location as a normal heat riser, but it is controlled by a vacuum actuator that bolts to the right hand side exhaust manifold. Vacuum is ported from the carburetor, through a TVS (thermostatic vacuum switch) which is located in the thermostat housing. When the engine is cold, vacuum is applied to the actuator which closes the exhaust heat riser which in turn forces the right hand bank of cylinders to exhaust through a port in the intake manifold. In passing through the intake, the exhaust gases pass under the carburetor in order to preheat the carb. The exhaust then passes through the left hand cylinder head and out the left hand exhaust manifold. When the engine hits 170 degrees or so, the TVS closes, depriving the EFE vacuum actuator which in turn opens the exhaust heat riser, allowing exhaust gases from the right hand side to flow normally.

This was done for two reasons. #1, it improves drivability when the engine is cold and #2, it shortens the warm up time. Since the warm up time is shortened, the amount of time that the engine is running in a richened state (and the resulting pollution) is reduced.

So, here's the problem . . . there is no practical way to incorporate the EFE heat riser into long tube headers. For that matter, I'm not sure there's a practical way to incorporate any heat riser into long tube headers. This is the reason why the manufacturers have not developed CARB certified headers for these years of vettes.

Now, if a guy wanted to be really enterprising, he could probably figure a way to use shorty headers and get the EFE controlled heat riser to mate up. I actually have a set of shorties that I goofed around with for this purpose. However, the heat riser ended up sitting low enough that it would have taken some real pipe bending creativity in order to hook up the head pipes. And even at that . . . bottom line . . . there would be no CARB certification and that is what California lives and dies by . . .

So . . . three years and counting . . .
 

Tom73

Well-known member
Joined
Aug 21, 2001
Messages
1,427
Location
Round Rock, TX
Corvette
73 LS4 Coupe - 04 CE Conv
I just looked on the Hedman site ( www.hedman.com ). They are showing their part number 68307, assume these are long tube headers as the have 1 5/8" primary with 3" collectors, as being 50 state legal. The footnote for these state 1975-1980 only, 50 state legal for these years.

I would suggest calling the header companies direct to see what they have.

tom...
 
R

rpounds

Guest
Footnotes according to Hedman on part #68307:

1 Without smog injection or injection heads.

45 Not legal for sale or use in California on pollution controlled motor vehicles.

I contacted them some months ago. Out o' luck again . . .
 

Tom73

Well-known member
Joined
Aug 21, 2001
Messages
1,427
Location
Round Rock, TX
Corvette
73 LS4 Coupe - 04 CE Conv
But the Emission Footnote K states: 1975-1980 only, 50 state legal for these years.
 
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rpounds

Guest
Yes . . . I saw the same thing several months ago. That's why I contacted them. The guy says "nope" . . .

So like I said . . . outta luck . . .

I wish . . . I REALLY wish that they were okay to run. I'd have 'em in a second . . .
 
G

GigiAvanti

Guest
Wish me luck

Well, I went ahead and told my mechanic to install Hooker headers. I called so many places, including Corvette Mike's and Hedman, all with the same results - there are no smog legal headers for a '76. I just couldn't see putting manifolds back on, plus it costs more. What kills me is the CARB# is only a stamp on the headers, it has NOTHING to do with emissions. What kind of scam is that??

rpounds: I'll let you know if I can get it smogged in this area.
 
R

rpounds

Guest
Doug's headers' application guide only shows Corvette up to 1974. This is for good reason. There is no EFE controlled heat riser on a '74. Sorry . . . keep looking . . .
 
Joined
Jul 23, 2002
Messages
151
Location
Sussex, WI, USA
Corvette
1980 330HP / 1963 L75 Roadster
An option you might want to explore what I did to my 1980 by picking up a pair of 1982 Corvette exhaust manifolds; $115 on Ebay. 1980 had 2" dump cast iron, 1981 had the same 2" tubular header style exhaust manifolds that GM used on the 1980 305 California C3, while the 1982 had 2 1/2" dump tubular header style with air tubes. I picked up a 1982 front y-pipe and rear y-pipe which allows me to use the 1982 high flow cat which has a significantly larger inlet and outlet than my original. As a plus the new cat weighs a heck of a lot less than the origianal. If it's not 90 degrees out this weekend I plan on installing the exhaust so if anyone is interested I can post the inlet and outlet sizes as well as the cat weight savings sometime this weekend.

For the record in Wisconsin a car must be 20 years old to be classified as a Collector or as a Hobby Vehicle. In either case you pay a one time fee of $140 for the special license plates, pass one last State visual and sniffer test then have the vehicle inspected by a State Trooper. After that the car is exempt from all tests for as long as I own it. I should be ready for the procedure in a couple of weeks.

Eugene
 

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