I have a ls/vtec that was balanced and blue printed, with oversized b16 pistons and bored out a tad to make it 1.9L. The head was not rebuilt from the looks of the seals. I noticed a leak in the vtec silenoid gasket and the cam seals are seeping a bit. My question is since the motor has 15K on the bottom end is the head whats causing the oil to blow by past the valve guides/valves into the combustion chamber? What do I need to do to pinpoint the problem. I want to go turbo soon so I want to figure out if the head needs all the gaskets and shit replaced or do a whole rebuild. Thanks somalia. My engine builder told me to checl the pvc valve first and see if it needs to be replaced, but he said its proably just blow by because of the high pressure during vtec, and its ONLY during vtec when this is happening. How do I pinpoint the problem? Compression test? Leakdown?