[I gox 440]

I have a 440 w/msd distb, hooker headers,edlebrok dual plane manifold. Im wondering what cfm carb to get and mechanical or vaccum secondaries? what are the advantages and disadvatages. any suggestions would be helpfu l!!

 

[Bummo]

Don't know what your gears or max rpm you might run but I would guess 750 CFM or less and vac secondarys would be good.

 

[bigdog440]

what year motor,truck,2wd,4wd? i have a 73 440 in my 78 2wd club cab.mp dist,hedmen headers,accel 330+ wires,msd blaster 2 coil,orange box and use a carter 750. the old motor was a mild 400 same electronix and a carter 750. great carbs out of the box almost no tuning.

 

[macario]

I have an Edelbrock 1406 600 cfm on my 440. Tune it to your altitude and you will be fine. Ask a good local speed shop what jets they recommend.

 

[Guest]

I'm running a 1405 Edelbrock on my 440. The engine is mostly stock, mild RV cam, dual 2.5 inch exhaust, orange box, stock distributor and square bore 413 intake. I like the eddy carbs because they are all mechanical secondaries and very easy to tune.

Chris

 

[duallycrew]

I have a 750 holly vac. secondary on my 440 in the dually. Was put on straight out of the box with no adjustments. Weight is a big issue between vac. secondarys and mech.

 

[67MIke]

I'm running a holley 750 vac 2ndaries also.

 

[Major Ramifications]

The advantages of having a vacuum secondary carburetor are that it will work with a wider range of engine sizes/ levels of modification, and is more forgiving if not tuned just right to your combination. The also cost much less than mechanical secondary carbs.
The advantages of having a mechanical secondary carburetor are that it will give you a lower 1/4 mile elapsed time if properly tuned to your combination.
If your engine is in a truck, a 750 vacuum sounds like a good choice.
Wycowboy, the Edelbrock carburetors secondaries are vacuum actuated.