My Evo build is at 40 over do I need a up size in the .030 Head gasket over the stock size one for my .040 over bore. Also I'm looking at replacing the base gaskets to something better than stock. What do the stock harley base gaskets measure at and do they squish and lose some thickness when everything is torqued to spec. I wanna be as close to a 30 squish give or take .028 to .032 area. Trying to make sure my CR is around 10 to 1 for my W6H cam. Give or take I'll be 9.8 to 10.1 area depending on everything measures right. Thanks
You are going to have to do some measurments first to know what you need.
Cometic offers .010" and .020" base gaskets. Their common size/range head gaskets are .030", .036", .040" and up. I.D. is 3.568" on an 80" Evo H.G.
John
I believe .027 on the head gasket too.
Cometic will make you any size you want , if shim stock is available .
They did a set for me 0.004 I think it was , really thin
:agree:
Thanks everyone for the help gonna go with the .020 base gaskets thru cometic so I'm not using the hd paper ones that weep more often. Both cylinders were turned to make sure everything is flat as were the tops and heads so everything should go together and seal well. And I'll have my target .030 squish within a couple thousands probably .032 or so. Thanks again
How much was removed when the cylinders were trued. That will reduce the quench (squish) dimension. That can be recovered by increasing the base gasket or head gasket thickness if necessary.
Measured everything after cylinders were cut. Took .020 off top of flat tops to get everything close to a .030 squish. CR will be close to 10 to 1 for the W6H cam. Lower end has 45k since reman from Harley will be at .040 over now have 108k on the bike. I take care of her but also run her hard. After this it'll be a big bore 131 Ultima or something similar.