i have used them on 462 4.280 468 4.310 489 4.310 496 4.310 475 4.350 509 4.500 525 4.310 548 4.530 572 4.500 so you can see this gaskets works i do not like the idea of using a thick gasket some thing like 0.65 + when making it rigth is cutting down the top of the pistons i have a mill and thats what i would do. i keep a way from copper head gaskets they can be a pain in the ass to get them to seal so in the long run the best info i can give you is over 20 years of using the 1017 felpro like i said if it s 4.375 bore and hase a chamfer on top most guys do this after it thas been bored and the deck pins can be off this will move the gaskets so all the sudden you can be off 0.40 or more so the 1017 fel pro start looking good