Greetings . . .

I am an old school kinda guy . . . but I am curious about why you would be interested in a high silicon 'cast' type piston if your plans include a turbo.

Modern forging techniques require way less silicon and produce a piston that stands up to compression forces and combustion temperature far better than 'hyper' cast pistons from the days of yore.

The Ross site discusses the particulars in detail:
Ross Pistons

Hypereutectics was a compromise when construction was limited to casting. Buy introducing silicon one could machine the cast slug to a tighter tolerance - since additional silicon limited the expansion of the piston in the bore. The trade-off was that the piston became more brittle so knock and chamber pressures needed to be controlled - since stress cracks would simply run wild through the silicon channels in the alloy.

regards,
stock49

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