Getting head Gaskets to seal correctly:
Figure 8 and head gaskets

I have found that the OE copper figure 8 gaskets do not compress one bit. The old ones that we have removed from engines are the same thickness as the new ones that come with new sets of AE powermax pistons and liners. They all measure .018" thick.

The steel gaskets measure .002" thinner and not only do they have a tendency to corrode, they don't lift the liners up high enough so they don't have the necessary projection and the engine will blow head gaskets.

We used to have a lot of problems with high compression race engine when there was .002" difference in liner projection in any two adjacent cylinders or if a cylinder measured higher on one side than on the other. We now glue a piece of copper wire that is .012" thick into one of the groves of the steel racing gasket with contact cement before we install the head gasket and use silicone sealer sparingly around the coolant passages.

Since we have been using this procedure, head gasket problems have totally disappeared! We torque the head bolts to 95# with permatex "never seize " on the threads and then retorque the head hot as soon as it is warmed up. It never needs to be tightened again. It is a sure fix. It even will seal a head that is a lightly wavy or weak.

In an emergency we have glued wire onto both sides of the gasket. With a steel gasket, we have found that .012 " is the ideal thickness, thicker will have a tendency to allow water to leak out the sides of the head gasket and up the head studs, thinner won't seal as well.

Regards, Greg Solow

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