302 casting on a set of 318 heads

depends on compression or blower rusty
4 bolts need all the help they can get- LA does have failures
heads dance around which is why 6 bolts on race motors
decks flex
IDK about LA but AMC produced extra thick decks for us on one months notice
they hand shaved the cores on the night shift, deeper bolt bosses also
we squared them up at whatever height we wanted
sent the blocks out with decks rough cut, they used the large bore "mexican" od on the cylinders for some extra cylinder thickness
The 252 Mexican motor had a larger bore than even the 4.0 which is 3 7/8
we ran 3 3/4 + .010 to keep cu inches under the Indy limit with the stock 199 3" stroke (Mexican production 252 used 3 1/2 stroke same as US 232)
on the Indy motors we used Bellevue washers for head o rings
head could dance around all it wanted- still held #4 1/2 in head bolts