The Stovebolt Site Forums The Shop Area Engine Shop 283 Carb recommendations - 500 cfm Holley 2 bbl?

Good to be back in Stovebolt Land!!!

I picked up another truck, a 1964 GMC Long Wideside. This one has a 283 in it. The old Rochester 4 bbl Q-Jet is pretty hammered. I soaked it then took it apart. The secondary throttle plates were rusted in place...not good. Before I sink more time and money into it, I got to wondering if the Holley 500 cfm 2 barrel carb would be a good match for the V8. I'm running the Holley on my other GMC with the 305 V6 and am very pleased with the results. Anybody out there know what the Q-Jet flowed? Is 500 cfm enough or too much for the 283? Any other suggestions for a resonable carb for this thing? The engine is stock, as near as I can tell.

Thanks in Advance!!!

First of all ,2 and 4 bbls are cfm rated using different test procedures.To compare the two,divide the 2 bbl cfm rating by 1.4, so the 500 cfm 2 bbl is really equal to a 360 cfm 4 bbl. The old Carter 4 bbl used on 283 Power Pak engines was rated around 400 cfm so...Q-Jets flowed around 650 to 800 cfm depending on application. In theory ,the Q-Jets air flap on the large secondaries will only flow as much air as the engine needs. In reality,the small primaries have you constantly opening the secondaries to get any power.
Some will say the large throttles of the Holley 500 2 bbl have poor throttle response compared to a 4 bbl with small primaries, but it ain't necessarily so if you do side by side comparison tests.

Tony,
Interesting info. on the 2 vs. 4 bbl ratings. I'm thinking of switching from two 1bbls to two 2bbls. Can you provide any comparisons there?

Mine is on a 230 L6.

Those edelbrock carbs are reasonable and you can re-jet to suit yerself. I have one on a 305 in a 64 chev and as they say, runs right out of the box.

I've been running the Edelbrock 1406 600cfm carb for 2 years.. i havent had problems with new ones, but have had problems after PO's tinkered with them. I'm not a carb fixer tho, so off to the store i go.

Rusty, compared to the q-jet they are a simpler fix, they are an old afb carter with some up dates.Compared to the fuel injection, the most trouble free set up i have seen.

Six for me. 2bbls and 1bbls are rated by the same procedure, different than 4bbls.
I've experimented with many carbs on my 261 powered 37 Chevy truck.I have a long article coming up in Inliners, but basically the Holley 2 bbls and 4bbls performed better than an equal Carter or Edelbrock.All the non Holley's suffered fron the same problem, a bog whem opening the secondaries no matter how much fiddling was done with air valves and jetting.On a larger better breathing 6 (292 Chevy or 302 GMC),the situation may be different as on a V-8.Some guys like the bog, they think it's pulls better after it clears, but it's actually slower.