Rochester Monojet Help

[OhNoJoe]

I woulod be interested in getting a pic from the front of that carb set-up. I can't seem to figure out how the choke rod is supposed to be bent and hooked up for my 292
I got some carb pictures you may want to look at

http://s221.photobucket.com/albums/d...2pulled077.jpg

[ST Dog]

Originally Posted by OhNoJoe

I woulod be interested in getting a pic from the front of that carb set-up. I can't seem to figure out how the choke rod is supposed to be bent and hooked up for my 292

I hop these help some. I don't know if the linkage has been bent over the years or not.

[68gmsee]

Originally Posted by ST Dog

A Q-jet just seams like over ill for a 250.
While the primaries individually are smaller, I would expect the 2 primaries would still be bigger than the primary on a 2 bbl, leading to more throttling losses.

Not to mention this truck is for my 14yr old, who turns 15 in September. I don't want it to be too much. So I don't anticipate any performance mods. The 2bbl is more for economy. The smaller primary allows for less throttling loss and more effective part throttle fuel atomization (same reason the 2 small primaries on a Q-Jet help with efficiency compared to a square bore carb)

If it was for me I'd be putting a Cadillac engine in it

For economy, I've found out that you won't get much of a change on these trucks unless you get drastic. I've heard estimates of anywhere 10 to 18 mpg. I squeeze about 16 on the highway on my 250 single barrel and I used to get 15 on my 69 with a 350/350 and a quadrajet on the highway. Both with slight tailwind.

The 2 barrel has larger openings than the primaries on a quadrajet. I used to have a 2 barrel and the gas mileage was dismal. If gas mileage is the main concern, about the only thing that may help is rear axle ratio change, overdrive transmission, HEI distributor and maybe larger tires.

[ST Dog]

Originally Posted by 68gmsee

The 2 barrel has larger openings than the primaries on a quadrajet.

While the primary on a 2bbl is lager than either of the Q-Jet primaries, it should be smaller than the combined primaries on the Q-Jet.

Q-jet primaries are 1-3/8" each, or 2.97 in^2 total area.
That's the same as a 1.94" bore. I tought most 2bbs had 1.5-1.75" bores.
I know Holley/Webber made some 2bbls with different sizes for the primairy and secondary.

And I want a vacuum secondary if I can find one, not a mechanical.


Guess I should start a different thread for trhis. It's off the monojet topic.