xr head gasket?

[USAF Dirtboy]

I am getting a xr400 head that is ported and polished and plan on getting a high comp piston with it... I was wondering if a xr top end gasket will be the best and the most reliable. thanks

[400exrider707]

You can use either gasket (the XR's or the EX's) The XR's is actually a little thinner and will bump the compression up more, so I guess technically its less reliable, but its still worth doing. In fact cometic sells a gasket that is even thinner than the XR one, I am running the cometic one currently. Either get the XR or the cometic one.:o

[F-16Guy]

If you're going to go through Cometic, call and ask for the thinnest base and head gaskets available for the 400ex. The deck height on the 400ex is too low to achieve the most efficient combustion, so using a thin base and head gasket will help close the gap. You can also go without a base gasket by using Honda's high temp gasket sealer. I really don't recommend this because the oil passage to the cam runs through that area, and you could have some leakage, or worse, you could block the passage with sealant that sqeezed into it when you tightened everything down. I would just go with a very thin base gasket. Thinner gaskets will raise the compression slightly, but it should actually make the engine run cooler because of the better quality of combustion (more of the "bang" gets turned into mechanical force and less into heat).

[cals400ex]

i would get the thin head and base gasket from cosmetic for your bore size you choose. C&D can get all of this.