Im throwing together a budget motor before summers over, now that I know how to shop for cheap parts. But the set of heads I have are the 624's, which Ive heard alot of bad about. But they look like they're in good shape and they were free, so I was considering using them. Ive got a good 350 shortblock with a Lingenfelter hyd. FT cam 216/218 .462/.470, Performer Intake, and a Double Pumper or similiar used carb when I find one. Will that combo even make 275hp with those heads? This isnt going to be a serious race motor, just a little somethin to mess around in and be loud. Even 250hp will do.

 

what pistons are in that motor? If it's a stock motor, stock pistons, and you'll be using a composition head gasket, the CR ratio will be flat out dismal with those heads.
I'd grab some 305 heads to bump up your CR... Port 'em if you have time.

Or, never thought i'd say it, some 305 swirl port heads. With that cam, and keeping the RPMs low, it'd be fun to drive around town with, for the summer at least.

 

The pistons I have are 4 valve reliefs with a slight dome around the edge. Im not sure now much it changes the compression.

 

No, what they actually have, is a dish in the middle.

You have one of the worst possible combos in existence for making power. Basically, it is an EXACT DUPLICATE of those rompin', stompin', ground-poundin' 165 or 180 HP 350s ( 2- or 4-barrel) out of the 70s. Call it 180, just to be optimistic.

Your CR is right about 8¼:1.

I'd back off on the cam a notch or 2.

Somehow, I don't see where a cam and a different carb are going to get you 100 more HP, more or less. I think even with headers, you'd be lucky to see 230 HP out of it, as measured in the same way that new cars are measured.

A motor like that is a perfect candidate for some of the better 305 heads such as 416s, with some 1.94" (stock 350 size, like the 624s probably have) installed in them. That ONE SINGLE CHANGE will take the compression into the mid 9s, and give you more flow than the old smoggers besides. That combo WOULD have the possibility of making 275 HP, and that LPI cam would then be appropriate.

 

aight. mabey Ill just take these heads to the swap meet this weekend.