Yep.. Many of the new powersports pistons from Wiseco are 4032 alloy instead of the other, softer 2800 series alloys. The RKT Wossner pistons were the higher-silicon-content 4032 alloy.
FWIW...
I called RKT and he confirmed that the new pistons in his kits are indeed Wiseco's... with the 4032 alloy, built to his specific design specs.
I asked him why he changed... he said that Wossner became unreliable for delivery ... and that Wiseco was willing now to build him his piston to the exact spec he wanted, and deliver on a reliable schedule. He liked the Wossner pistons, but the delivery of what he ordered didn't work with running a business on a schedule.
He also said that he is very happy with what he's ordering from Wiseco now, and their ability to provide what he needs on a timeline... which was not the case in years past for him... things change and businesses evolve.
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