Got a question on which head gasket to use after having cylinders bored. I have the top end off right now as i was blowing a little smoke from rear jug and decided to rering and a valve job. Found the rear jug was .006 out of round and had to bore the cylinders .010 over, got new pistons and rings (.010 over) and the valve job is done (also found a cracked valve guide on rear head). My question is should i use a stock size head gasket or go to an oversized. This is on my 96' Heritage. Thanks for any and all input on this. Bully

 

I can't answer your question, but you might want to post this in the EVO classics section also.

 

Stock size and thickness is fine, most prefer MLS gaskets. (multilayer steel). I used James gaskets for my rebuild, and was very happy with them.

 

Think about it; .010" increase in bore diameter is only a .005" difference all the way around the bore; use the OEM head gasket. MLS, like Cometic, is also a good suggestion and I would add that you consider a thinner head gasket, like .030", for a modest boost in compression.

 

Thanks for the replys guys. I was hoping i wouldn't need to get different gaskets. I already had bought a James top end gasket kit with the .045 head gaskets, now DJL has got me thinking about the .030 gasket. Is there really that much differnece in the two gaskets that would make it benifical to order different ones. Thanks again.

 

The .030" gasket will bump compression about .25 points above stock and improve squish which facilitates a more complete fuel burn. Cometic makes a good gasket but you can buy them cheaper from other sources, like CYCO gaskets; about half the Cometic price. Worth it? That's your call; it would be to me.