What kind and where can I get a good set of aftermarket pistons for a turbo app? Does any other work need to be done for pistons that are bored/oversized?

 

Forged Aluiminum high Silicone content pistons of no more than 9.5:1 compression ratio
Start reading up here:
http://www.importperformanceparts.net/

On a turbo application, for oversized pistons, you want to go oversized pistons and Sleeves. You don't want to reduce the sleeve thickness, it not only weakens the sleeve but effects piston cooling as well.

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