Thanks for the information. I am learning a lot. I measured the two 477 heads - and the port sizes are different on each.
The 302 head has 1.75" intake and central exhaust ports. The end exhaust ports are 1 3/8".
The (1946) 228 477 head has 1 3/8 intakes and 1.75" center exhaust ports. Same 1 3/8" exhaust ports on the ends.
So there are two variations of the 477 head - a large port and a small port head.
My intuition says that the larger port would be best for a 270 bored at .060. But you say the small port head will be fine.
Perhaps the small port head would be fine for street use. Can you help me understand this?
You may be right - it could be a 1957 270. This engine had a cast iron mount that was fit to a machined flat boss on it for a compressor and a 3/4" drain hole drilled into the block just forward of the fuel pump.
Cast code is G247. Serial number is 270 829597.
Pistons, rings and bearings are new. Wasn't used after rebuild. Just put away in a barn as a short block, and now I am cleaning it up.
Last edited by Hunterdude; 11/04/19 04:08 PM.
