Hey all, I know I am searching for that unicorn. but thought I might ask. Does anyone have the Steel shim head gasket for a 455? I am trying to get a .020 to .030 thickness. Copper or MLS is fine too. Update: I made a discovery while doing some research. Can steel shim head gasket be used in a 455 block/430 head combo? block is a 74 Thanks
The GM/McCord head gaskets will only work on 72 and older blocks. If you need a thin head gasket on the 73 and newer blocks use Cometic head gaskets. Do not use Cometics unless the block AND heads have been milled with CBN cutters! If will be cheaper to mill the block or heads! Thanks, John
The block is a 74, with 69 Heads on it. It looked like the block has been milled before since the numbers were not there anymore and did see some sort of cut lines in them too. Not sure about the heads, They are in the machine shop now. Would these apply to my combo set up with the 74 455 and 430 heads? http://raybarton.com/parts/index.php/cometic-buick-400-430-455-head-gaskets.html (FYI this set up came off an already block that I had purchased, So all the modifications have been done as in plugging need holes for it to work) I have thought about milling the block and heads, problem is. I don't know how much was taken off the block. And How much would I need to take off the Heads??? I know I need a certain quench and don't want to take to much off the heads just for valve clearance....or should I be fine? Thanks Also what is a CBN cutter?
