Wossner FORD 2.0 Cosworth YB Turbo 91mm 4x4 8.0:1 Forged Pistons Set. 91mm Bore Pistons. Wössner pistons feature a unique PTFE coating on the skirts and a grade of 4032 Alloy (T6) which allows the engine builder to run a closer piston to bore tolerance then he might do on another make of piston.
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