Those are 360 smog motor heads i wouldn't put two cents in to them,i 've got a pair sitting on the garage floor cause' thats about all they're good for,holding the door open..try to find a better set of heads...
thanks a lot,, you saved me... anyone out there have a extra pair of J heads they can let go of???,, seems thats what most people say I should use to get maximum HP out of a 360