Smaller Gaskets to Boost Compression?

[USAF400EX]

Hey guys. Just wanting some more info on running the Cometic head gasket and something else for the base ? Has anyone done this mod and noticed any difference? Seems like a cheap way to get some more oomph.

[400exJOE]

i have a cometic head gasket and I believe its te same thickness as stock (.025?) If you want to increase your compression, you can use an xr400 head gasket. Your compression will go from 9.0-1 t 9.3-1 with the stock piston. I can't believe thats worth tairing down the top end for.

I believe that the stock EX head gasket is about .040 and the xr and cometic gaskets are around .025. If you remove the base gasket, which is .020 and use Honda high temp silicone you should gain at least .015. This adds up to about .030 and should move you up from a stock 9.1cr to about 10.0 on a stock bore.
Good enough to get a xr cam since you've got to remove the cam anyway. Then you will notice a significant increase in power!
BTW- I'm going to do just that tomorrow and will post the # on the "have you decked the cylinder?" thread as soon as I figure out how to add and subtract. :confused: