Current GM Q-jet Rules

[J.R. Haddad]

OLDSKOOL, you are overthinking this topic. ANY q-jet as long as it
measures correctly. PERIOD. J.R.

[Bob Mulry]

When Edelbrock was a Major Sponsor with the Q-Jet replacement carbs, NHRA changed the rule to allow Edelbrock to sell more carbs......

The B-O-P guys could by an Edelbrock carb to replace the front inlet style....

The phrase "stock inlet location required" was removed from rule book…….

Show me the money and I'll show you a rule change.....

In Stock AFTERMARKET disc brakes, aluminum seats, intakes, heads and radiators, transmissions, 6" clutches, 2 year seat belts and on & on & on......

[oldskool]

Originally Posted by J.R. Haddad

OLDSKOOL, you are overthinking this topic. ANY q-jet as long as it
measures correctly. PERIOD. J.R.

Got it. Thanks !

[oldskool]

" When Edelbrock was a Major Sponsor with the Q-Jet replacement carbs, NHRA changed the rule to allow Edelbrock to sell more carbs..."



So far, I've never read exactly what years the Edelbrock Q-jets were made. I did find this article that says they bought a new one in 1997.

http://www.hotrod.com/articles/edelb...or-replacment/

And this site says production was stopped in around 2002.

http://quadrajetparts.com/edelbrock-...tors-t-10.html

So, I assume production began in the early 1990's. Does anybody know, for sure ? And, the exact year they were made NHRA legal ?

I know now that any correct size Q-jet is legal. But, I'm still curious about the E-Q-jets & the rule change. I was out of racing so long that before I learned to use a computer, a few years back, I'd never even heard that Edelbrock sold Q-jets. And, by then, they'd been out of production for several years. So, ya'll please excuse my ignorance on this subject.

Thanks !

[Hacksaw]

Hey Oldschool: I was told by a very reputable QJ carb guy that he did not see any performance difference between an Edelbrock or GM 207 carb and he preferred the Edelbrock because usually they were nicer cores to start with. Good time to check the classsracer parts section. Good deal there on what you need.

[Dwight Southerland]

Part of the distinction with the Qjet carbs is that all the GM carbs were manufactured by Rochester, which means they are the same make and model. The Edelbrock replacements are listed in the Accepted Products publication under Carburetors along with Edelbrock's AFB replacements and the QuickFuel replacements. They are listed distinctly because they are different manufacturers (make). No need to list all the carbs by the OEM manufacturer.

[ss3011]

Carter made them for GM back in the mid 70's too .

[oldskool]

Originally Posted by Hacksaw

Hey Oldschool: I was told by a very reputable QJ carb guy that he did not see any performance difference between an Edelbrock or GM 207 carb and he preferred the Edelbrock because usually they were nicer cores to start with. Good time to check the classsracer parts section. Good deal there on what you need.

Yeah, they are quite a few years newer than the GM Q-jets. That alone should mean that a larger percentage of 'em are in better shape.

And thanks for the heads-up ! But I already have a couple of E-Q's. And there are always several for sale on Ebay.

Also, have a small stash of GM Q-jets, and access to lots more.


" Carter made them for GM back in the mid 70's too. "

Yeah, Carter made LOTS of Q-jets, in the '60's & '70's. Their name is cast into driver side of the main body. " MFG. BY CARTER CARBURETOR FOR GMC ".

[oldskool]

While we're on the subject, I've got more questions.

(1) What is a ballpark figure that one of the good class car Q-jet builders would charge to build a Stocker type unit, using my core ?

(2) Aprox how much quicker is a Q-jet which is built by one of the top class racer guys, as compared to a good average street/strip or bracket race build ? Just wondering if it would be worth the extra $$, if all you wanted to do was just be able to run slightly under your index, rather than building to win all your heads-up races. (Not looking for any good buys on ready to race carbs--just gathering facts.)

(3) In pics I've seen, it shows the choke plate still in, Stock & SS. So, is it a rule that the choke plate must remain ?

(4) Haven't seen any pics of the Stock & SS cars running an air cleaner. So, aprox how much power is lost by using a good air cleaner set-up ? I assume there have been lots of dyno and track tests for this, thru the years.

[Bob Mulry]

The statement "stock inlet location" was included in my 2003 NHRA Rulebook......

The statement was no in my 2005 NHRA Rulebook....

I can't find my 2004 rulebook...

So the inlet location requirement was removed in 2004 or 2005.....

Because B-O-P and Cadillac that came from the factory with a front inlet now could run a side inlet carburetor.....

Edelbrock only sold side inlet carburetors...This rule change greatly increased their market......

The oldest rulebook that I can easily put my hands on is 1995 and at that time it was restricted to the size, inlet location and external appearance. Computer carbs could be replaced with non-computer with the same size bores and venturi...

Hope this helps,
Bob