Quadrajet on a 292 straight-6 ?

[Asshat]

These Quadrajets are pretty easy to find and work on; wondering if anyone has ran one of these on a 292? Quadrajets can range anywhere in between 600 and 800 CFM, just not sure how to identify these.

[geezer#99]

Quadrajets are 750 or 800 cfm.
Easiest visual clue to difference is the fuel inlet. 800 cfm carb the fuel inlet was straight in from the front, 750 was from the passenger side.
The 750 should work well. Pontiac used one on their sohc 250.
Easy to adjust secondary air door to control any bogging.

[cwcarpenter98]

I haven't ran one on a 292, but I love the one on my 283. I get better gas mileage with it as well (if I don't rev it out all the time )
I don't know of anyone making a spread bore intake manifold for the 194-292 straight 6 family. You could easily add an adapter to a square bore intake though.

The other tricky thing would be the throttle linkage. I would think that the carb mounted with the front pointed towards the passenger side would be the best way to get full distribution of air and fuel when on the primaries and also the secondaries.
That would be a complicated mechanical throttle linkage setup, or you could convert to a cable style pedal. I converted my pedal when I swapped to the Q jet. I used a squarebody pedal, but the 71-72 c10 pedal fits better with the contour of the firewall. The cable can make that 90* turn a lot easier than mechanical linkage can

[old51sedan]

I'll currently working on installing a Holley on mine, but have decided to turn it to face the front of the truck. It is a 550 CFM, the primaries are quite smaller then the secondaries. I also just removed a complete gas pedal assembly with cable from a 70's Cadillac to install in my truck. It will be interesting as to how it all plays out. here's a picture of it.

[Asshat]

Originally Posted by old51sedan

I'll currently working on installing a Holley on mine, but have decided to turn it to face the front of the truck. It is a 550 CFM, the primaries are quite smaller then the secondaries. I also just removed a complete gas pedal assembly with cable from a 70's Cadillac to install in my truck. It will be interesting as to how it all plays out. here's a picture of it.

Cool! Where did you get that intake manifold?

[68Gold/white]

If you do carry this Q-Jet deal through on your in line, I'd advise you to contact Cliff for parts and assistance. The smaller engines CAN use a Q-Jet but may take some tuning time...

[Asshat]

Originally Posted by 68Gold/white

If you do carry this Q-Jet deal through on your in line, I'd advise you to contact Cliff for parts and assistance. The smaller engines CAN use a Q-Jet but may take some tuning time...

I ahven't dcided yet on a Q-Jet for sure, still thinking about a Rochester 2bbl. Really no sure which way to go.
I heard so many have been successful with the 1bbl; guys say it just pulls like a freight train. It should still run better with the carb I have, just gotta figure out why it's so sluggish, but, that's another thread.

['68OrangeSunshine]

GM of Brazil used to make a stock cast iron intake to mate a Q-Jet on an L6. They sell pure cane alcohol there as auto fuel. It takes a higher alcohol/air mixture to get the same caloric value as a gasoline/air mixture. So a 750 CFM alcohol carb would be needed where a 390 CFM gas carburetor works.
Only seen the pictures. Don't know any Brazilians.
I'd rather drink it as Rum, than burn it.

[GASoline71]

Originally Posted by geezer#99

Quadrajets are 750 or 800 cfm.
Easiest visual clue to difference is the fuel inlet. 800 cfm carb the fuel inlet was straight in from the front, 750 was from the passenger side.
The 750 should work well. Pontiac used one on their sohc 250.
Easy to adjust secondary air door to control any bogging.

I thought the straight front inlet was a B.O.P. thing and the passenger side inlet was a Chevy/GMC thing?

Gary

[geezer#99]

That’s true but 800’s had only straight in line.
Easy way to know at a glance.

[D13]

Look for one off a 4.3 V6. Block out the computer solenoid and go.

[SilverMiner]

Originally Posted by geezer#99

That’s true but 800’s had only straight in line.
Easy way to know at a glance.

I'm reluctant to argue with a geezer, but I dislike false info even more. 800CFM Quadrajets have been installed in every make of GM vehicle including Chevy and GMC while only Buick, Olds, Pontiac & Cadillac have inline fuel lines due to the location of the water neck on Chevy's & GMC's requiring the 90 degree turn.

BOPC engines could have either a 750cfm or 800cfm Qjet, just as on all small or big block squarebody truck engines. The only defining characteristic of 800 vs 750 quadrajet is the diameter of the outer primary venturi ring which is a mere 4/32 of an inch larger. Fortunately, this very slight difference is reflected as a small bump visible in the outer ring. Staring carefully down the primaries with the choke flap open can reveal the secret. See the attached photo.

[geezer#99]

Not false!
Incomplete maybe.
He was looking for a way to know what the carb is.
I give him a couple visual clues.
I guess I coulda included the Venturi difference but it’s likely he and a hundred more people on here couldn’t tell you with a look inside which is which. You can, I can. Most can’t.
Sometimes you need to answer the question and not get too deep.
That just confuses everybody.

So with that said I apologise for leaving some things out.