have a set of heads that I am trying to figure out what they are. I know they are 302 heads they have D60E Id numbers. I really would like to know what style rocker arms they take. The rocker studs bases are about 3/8 but have 5/16 threads. Can some one help
Just your std run of the mill 302 heads. The studs are the "positive stop" type and use rail rockers. The shank is larger than the threads, these were non adjustable, but can be made adjustable just by placing a thick washer under the nuts. But don't get the idea that these are Ok for hotter cams, the studs are still pressed in the head and will pull loose with more aggressive than stock cams.
If they are 5/16 threaded they are the late style pedestal rockers. Still not adjustable but better than the earlier press in design. You need a set of pedestals and sled type rockers, not the earlier rail type if this is the case. The sled fulcrum design was introduced in '77, so it's not unreasonable that a D6 ('76) casting was used in a '77 build.