So here is my question, I currently have a new set of Cometic head gaskets. There are the .040 compressed gaskets. A buddy of mine said that since I am using a 6.0 iron block that I need to use the .050 head gaskets. What do ya"ll think? Just wanted to double check before I order another set of gaskets.

 

You can use whatever thickness you want. You just have to be sure you know what your size your heads are and your piston size and whatever your target compression rate is. You can use the compression calculator on Summits site to determine what head gasket thickness you need to reach your compression. But I will say .040 is kinda thin and stock probably is around .050.

 

You need to figure out what you want the motor to do, then determine your target CR.

You will need to know, How big in cc's are your combustion chambers, the volume of your pistons in cc's, the down bore depth +/-, what size bore are the head gaskets you have, the bore and stroke of your engine. That will be the start, add in your head gasket thickness. That will give you your CR for that head gasket compressed thickness. Simply change the gasket compressed thickness and bore to change the CR. There are limits each way that you can go with the thickness before you encounter or run the risk of encountering problems.

 

Need to know piston CC's, heads and combustion chamber cc's, and cam to even begin to wager a guess.

 

Well, my piston cc's are -3, according to the Wiesco sales guide with 65 cc chamber heads they should yield me me in the neighbor hood of 11.8 with a .040 head gasket, and 11.5 with a .050 thk gasket.
Cubic Inch will be 408
Bore 4.030
Stroke 4.0''
Rod Length 6.125''

I just heard that it was not recommended to run the .040 with an iron block.

 

Give Cometic a call, they should know what their gaskets are suited for but I never seen any info on iron vs aluminum.

 

Need to make sure you have head to piston clearance. As long as that is good run the thin gasket.

Tim

 

Yes stock is around 0.054 but a thinner gasket like that is not "too thin". Plenty of people run that thickness.

Who said that?

I would trust whatever the the actual designer and manufacturer of the part says over some random dude. Like mentioned previously, call Cometic and see what they say.