Okay i have read the sticky but what i am wanting to know is whether they will go straight on or any modding? Engine as of now is stock '75 buick 455. What horses am i looking at roughly? any other advice will help. I got these heads because i thought they had the highest compression and only to find that 67-69 had the highset (besides i think 1970 stage 1 @ 61cc).
There shouldn't be a problem as 70 and 75s both oiled through the push rods. If I remember correctly you need to use 70 head gaskets with the 70 heads. As far as horse power it depends on a lot more information than you are giving. What other mods are being done to the engine. Good Luck. Bob H.
Are the 455's different from the 340 in the way they adjusted compression? with the 340 they did it with the pistons, heads where the same, unless you mean flow rather than compression.?
70 head gaskets (.020" steel) will only work with the 70/71/some 72 455 blocks with the single scallop and will not cover the later double scallop's (some 72's and 73-76) oblong coolant holes on the decks. As a side note the heads made for these double scallop blocks if to be used on a single scallop block need a coolant hole plugged or will dump coolant into the lifter valley. Felpros will work as well as other aftermarket head gaskets for all year combinations as long as these precations are taken. Ray
Just as Ray said, all you need to install 1970 heads on a 1975 block are aftermarket head gaskets. See:http://www.gesslerheadporting.com/gesslerheadporting/ghp.nsf/top-menu-items/ghp09 . Devon
Wow guys! Thanks! This is exactly what i needed to know i really appreciate the love from this fam! Happy New Years!
