Somebody said you should thicken the head gasket to lower the compression ration since the car is not designed for high compression, I feel that this is a false. However, the change of cylinder head gasket sounds a good remedy. The O ring I heard in installed in the spark well in the cylinder head. I'm not a skilled mechanic. I only read and apply as appropriate. I also installed a mechanical boost Gauge and it reads around 8 psi of pressure. I guess that this is not that much. You would imagine the power gain I got. it sound as V8 engine, and even more power.