Headers and updating carb

[soxx35]

I want to install headers to my 79 l82 what adjustments should i make to my carb to make up for the better breathing engine. The carb is a stock quadrajet.
thanks rj

 

[81 Corvette]

when i installed my headers, i had to richen my Demon up just a tad

 

[76 Sting]

I want to install headers to my 79 l82 what adjustments should i make to my carb to make up for the better breathing engine. The carb is a stock quadrajet.
thanks rj

Hey.... finally a RI man!!! I live in Narragansett! To answer your question the carb should not need any adj. Headers are a way to remove the pressure from inside the engine more quickly (in most cases). Just a little advice, you may not want to change the stock manifolds. I did and lost some good torque out of it.

I was catching 2nd gear (automatic trans) and the day after I installed the headers (no leaks and 1 5/8 primary) I was not able to catch it again until I installed a new manifold and carb. The manifold exhaust on the C3 corvette were some of the best ever made and is due to the larger exhaust opening than normal Chevy’s. I believe it is a 2.25 or 2.50 inch opening.



Good luck...hope to see you at some of the car shows in RI. I will be at the Garden City ones this year for the first time, every Mon night.

 

[JohnZ]

Generally, adding headers (with a low-restriction exhaust system) calls for slightly richer jetting, although the potential benefit of headers is pretty much wasted with a stock exhaust system and won't make much difference.

The stock ram's horn (and later tubular) exhaust manifolds on all small-block Corvettes from '66 up through '82 have 2" outlets; '65 was the last year 2-1/2" outlet manifolds were used.

 

[74bigblock]

Get sidemounts and side pipes

 

[RodsnRides]

Headers = PITA

soxx35, I recommend you keep the stock manifolds and go with a true dual system woth some Flowmaster 40's or similar. I believe you'll find a thread in here about using a 1974 crossmember for the dual pipes. Headers, unless you really plan on flogging it, are a pain. Hard to get at the plugs, burned wires, sit too low (real speed bump detectors) and just generally a hassle. But, they are a performance gain-if you combine as a package (cam, intake, etc.). Have not tried "block huggers"-they may be an alternative.

John Z-I thought the '70-'72 LT-1 cars had bigger exhaust openings than the 2" on the "regular" SBC's. No?

Best regards,

Rick

 

[81 Corvette]

soxx35, I recommend you keep the stock manifolds and go with a true dual system woth some Flowmaster 40's or similar. I believe you'll find a thread in here about using a 1974 crossmember for the dual pipes. Headers, unless you really plan on flogging it, are a pain. Hard to get at the plugs, burned wires, sit too low (real speed bump detectors) and just generally a hassle. But, they are a performance gain-if you combine as a package (cam, intake, etc.). Have not tried "block huggers"-they may be an alternative.

John Z-I thought the '70-'72 LT-1 cars had bigger exhaust openings than the 2" on the "regular" SBC's. No?

Best regards,

Rick

i disagree. I have no problems getting to my plugs or with burnt wires. While they do sit slightly lower then the manifolds, i rarly scrape any worse tehn i did before. The headers gave my car a nice performance boost. I'd recommend em all day long. I've got the ever popular dynomax ceramic coated

 

[Bob Chadwick]

I have no problems getting to my plugs or with burnt

I agree. They are slightly tighter and I can't get a ratchet in there. However, I have a plug socket with a nut like configuration on the end and simply use a standard wrench.

I have headers and a slightly improved flowing intake and developed an intermittent miss at high speed that may be related to a lean condition in the carb. I'm taking it in this weekend to have slightly richer primary jets and other adjustements to hopefully make this problem go away.

 

[RodsnRides]

Fair enough

No argument here. With the later SBC's you are talking 5/8" taper-seat plugs. My frame of reference is the earlier 13/16" plugs with seat washers. Have not worked with the Dynomax headers, either-perhaps they make some allowances.

I used to cuss the #6 plug most often. That one was a bear to get at using a variety of wrenches. NO WAY was a socket going on them-hex ended or not. :ugh Appliance Black Jack, Hooker Comp and Super Comp, Stahl, Thorley. I agree that later designs are out there.

In the scheme of things, it is what the owner desires. Serious street performance, warmed-over driver, drag racer, whatever. This desire, the checkbook and willingness to make concessions due to choices (fuel quality, tune-up frequency, driveability, etc.). This discourse is not limited to exhaust choice, of course.

I have headers on 3 cars. I don't on several others. It's a matter of choice, particularly when you get into cars equipped with options such as A/C and power steering. Some headers won't accommodate a standard transmission-the FloTech Tri-Y's in particular.

Rick

 

[Bob Chadwick]

As the saying goes "what seperates the men from the boys is the price of their toys." :L

 

[RodsnRides]

Price, yes, or...

...I like the one about "...the MOST toys"...

Rick

 

[Bob Chadwick]

I like that one as well.