they're closed ch so it'd bump the CR up a bit which'd b good 4 you if you could find a set 4 cheap/ready 2 go as you wouldn't want to put alot into them.Prob some mag heads would b more practical but you need a mag manifold as I dont think you want to redrill the heads' intake holes at this point. Not sure on the 302 yrs avail but it'd b better to find a set of them (or mags) 4 sale ready to bolt on & a set of early 273 heads which are closed ch would b good & nobody wants them. do some searching & get a good bargain