Head or cylinder shims?

[Classic Manx 71]

I'm starting to reassemble my 1835 cc engine which had a set of cylinder-to-case shims installed before. They seemed to work fine before but were a little messy to install using RTV sealant. I have a new set of them but also have a set of copper head-to-cylinder shims of the same thickness. Which are the best to use? Do the copper shims seal better? Any personal experience out there? Thanks.

[bobaganoosh]

I always spray shims and gaskets with copper spray sealant instead of rtv.

I used it on my mustang when I blew a head gasket and it hasn't happened since.

don't know if this helps ?

mike

[Hawk]

What is the deck height? This will tell if you want to use the barrel shims or head seals.

[David O']

ALWAYS use cylinder to case shims.....never use the head shims. There is too much difference in the coeficiant of expansion between the heads and the cylinders, for the shims to STAY sealed. (This is why I have NEVER understood someone lapping the cylinders to the heads and saying that it is for the guantee of sealing the heads.) Also, you don't want to take the squish out of the heads which helps to get the fuel to burn better, and more completely! That is my two cent's worth!