During block prep, always check piston projection above the deck surface with a dial gauge before choosing your head gasket. On early 4HG1 builds, matching the 5-layer laminate prevents over-compression and localized cylinder ring distortion. Ensure all head bolt threads are chased clean and lightly oiled so torque-angle tightening draws the cylinder fire rings down uniformly.

The kit provides complete high-temperature sealing across the long block. The crankshaft rear main seal is molded from reinforced fluoroelastomer (FKM) to resist high crankcase heat without hardening, while intake and exhaust manifold gaskets are fire-ring reinforced to handle severe turbo exhaust manifold expansion.

When installing the valve stem oil seals, use the protective plastic sleeves over the valve keeper grooves. Pushing stem seals dry over sharp valve stem notches causes micro-tears that lead to oil burning and blue smoke on deceleration.