I'm thinking of replacing my 2 barrel system w/a 4 barrel setup on the 292 in my 57 truck. Engine is stock except for installing headers and noisemaker mufflers. I've been checking out manifolds and carbs on EBAY, supposing all y block manifolds will swap out w/each other. Anybody got any recommendations for a carb? I'm not sure what a good cfm rating or part number would be for the swap. I'm going to go w/a rebuilder carb, anybody got any suggestions for type and application fit to manifold ?

 

Not all 4V manifolds are the same, 55-56 use a small square bolt pattern for the earlie Holley teapot/Carter/Rochester type carb and smaller intake ports. 57 and up use a spread pattern for the newer type 4150/4160 Holley and have larger ports. I run a Holley 390cfm on my 292 with a mild cam and its plenty of carb for everyday driving.

 

Thanks Jim, was the Holley 390 original equipment back then ?

 

I don't recall what the CFM was on the originals, mine is a new one, vacuum secondaries, electric choke model. Most of the original type are harder to find and so worn out they aren't worth rebuilding unless you are a purist so I just bit the bullet and bought a new one.

 

I doubt it. I had an original 57 Holley, can't remember the nymbers. Those 390s are expensive and have all the bad habits of every Holley, gaskets that seep and leak after a couple years, finicky electric choke.... For the money, I'd find an Autolite 4100 from a small block Ford. Much more reliable.

 

You want an intake with the square bore pattern. The factory manifold will have ECZ-9425-B on it.

However, these are getting ridiculously expensive - for only a little more, you can get an even better aftermarket aluminum manifold from http://www.ford-y-block.com

A more cost effective option is to get the ecz-9425-A manifold and use an adapter for the square bore carburetor. This will leave some performance potential on the table but with much less cost, and should still be a nice upgrade.

For the money, the Summit carburetors are hard to beat. The 500cfm should work great, and give you a little room to work with for other upgrades. The most important thing with any carb is to tune it.

 

Just how ridiculously expensive are they? I just made a deal on a 239 with one on it and a brand new Edelbrock carb. I know of a few more around, not saying they can be bought but you never know.

 

Like most things, you can still find them at a good price, if you are patient or get it with an entire engine but for the most part, they go for about $350.00.

I doubt you have a 239 with the B intake on it. The port mismatch is too significant. It's either an early intake with an adapter or it's not a 239 that the intake is on.

 

It is a 239, setting in a 54 glass top (or at least it has 239 heads with the freeze plug in the end), and it's definitely a cast iron square bore intake without an adapter. I haven't checked the numbers yet.