The Stovebolt Site Forums The Shop Area Engine Shop Carb choice for a 292 with the 264 cam

I'm building a 292 .30 over with a cliff cam 264 high torque, I'm thinking I want a 4 bbl carb any thoughts on type and CFM, the cfm calculator I found goes 488 street and 690 full race. I don't want to be over carbed for drivability, but I want power, just a good balance the best of everything, is that to much to ask for. The 292 is going in my 47 3/4 bolt, P/U.

I put a 400 CFM Carter AFB (part number 9400s) on a 300 CID 6 and it was plenty of carburetor.

Jon.

the cfm calculator I found goes 488 street and 690 full race

Way too big. What numbers did you use?

i have the same cam in a .060 over 292. i settled on the edelbrock 500 cfm carb for mine. heard it was a toss up between that one and the holley, 400cfm i believe, for mild performance. i think the edelbrock was cheaper- i tend to cheap out a lot. i'm sure carbkings afb suggestion is just as good, or even better. mine runs really well with this set up. i'm sure someone more in the know could get it even better.
intake choice comes into play too. the clifford is really large and requires heat to run well, i have been told. wish i would have bought one already set up for that, i had to mill a box and weld it on the bottom of it. good luck whatever you go with.

I used 292 CID even thow it's .30 over, and 6800 RPM. I think I used Sumit Racings Carb calculator the 6800 may have been to high, I usually never drive a vehicle over 3200 rpm I think it works them to hard. But this is a special truck and I'm sure I'll rev it up in driveways and parking lots.

It isn't likely that you'll see anything over 5K on the tach unless this is a professionally built full blown racing engine with a short life expectancy. Some race engines will actually hit 7K but they aren't found in street machines.

I have been told that a raod deman Jr. which is 525 cfm would be the best thing ever, I'm a quadra-jet fan, I think thats edelbrock now, I don't want to over carb this thing. I am still in the market for an intake, are there more choices than the Cliford or the Offy. I'm planing on running a 200r4 behind it, not sure what gears yet. I have 3.08 in it now, I'm sure I'll go to around 4.10s. Thanks for all futher input.

Find your self a two barrel 350-400 cfm carb. You don't need anything fancy either. Keep it simple.

O.K. thanks, I do like simple, but what about the fuel mileage, if I use a 4 bbl carb I've herd that normal driving fuel mileage is better with the 4 bbl because you can stay out of the secondary. I'll be on the look out for more information on intakes and carbs for this motor.

From what I've been told the Road Demons are poor on fuel economy. But they sure are pretty. If your determined to have 4 bbl most who've done it stick with the small Carter. Ask Carbking. Look him up in the members area and send him an e-mail. He knows his apples.

I used 4500 RPM as a redline for a street engine with a .8 volumetric efficiency; and 5000 RPM for a race engine with a .9 volumetric efficiency.

For the above:

Street - 298 CFM
Race - 388 CFM

Once upon a time here in Missouri, there was a hillbilly with no shoes. At age 17, his uncle volunteered to buy him a pair of boots. The kid walked barefooted to town and came back wearing a pair of shiny new boots. His uncle asked what size. The kid answered. "Well, the salesman said my size was nine, but 10's felt so good, I bought 11's".

The same can be said for carburetion.

As I mentioned above, I placed a 400 CFM on a 300 CID 6 with a 4 speed. The truck would not run fast enough to engage the secondary in fourth gear. The 400 was plenty in the other 3 gears.

Fuel economy over the original 1 barrel Holley almost doubled! But that may not be the norm. The 1 barrel was really restricting the engine. The four barrel, coupled with some better exhaust allowed the engine to breathe.

Jon.