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SkunkLookingCar · 05-20-2011, 03:35 PM

Congrats on getting the engine together. What alloy are the pistons. 15psi might be a bit high for 4032 (ask enkivette) but 2618 will be able to handle the cylinder pressure. The valve reliefs look like they get pretty close to the edge of the piston which can be a stress riser. The thermal coating will help quite a bit though. The coating slows the annealing process that happens to all aluminum pistons when the temperture rises. Microhardness surveys of used pistons show the area of the piston where the valve reliefs come to the edge are the first areas to soften and the coating will keep the heat out of the metal keeping the piston stronger, longer. I agree with 94cobra69ss396 statement about the compression ratio and his suggested solutions.

05-20-2011, 03:35 PM	#14
SkunkLookingCar Member Join Date: Nov 2010 Posts: 92 Tweet	Congrats on getting the engine together. What alloy are the pistons. 15psi might be a bit high for 4032 (ask enkivette) but 2618 will be able to handle the cylinder pressure. The valve reliefs look like they get pretty close to the edge of the piston which can be a stress riser. The thermal coating will help quite a bit though. The coating slows the annealing process that happens to all aluminum pistons when the temperture rises. Microhardness surveys of used pistons show the area of the piston where the valve reliefs come to the edge are the first areas to soften and the coating will keep the heat out of the metal keeping the piston stronger, longer. I agree with 94cobra69ss396 statement about the compression ratio and his suggested solutions. __________________ Easily entertained.