black944 turbo

Stupid question but I just tore down the engine that is going in the 57 Speedster I am restoring and the cylinders looked very large. I check the diameter and they are 85.9 mm. I am assuming that this car has an 86 mm big bore kit. Can someone confirm this and what type of power should I expect with a standare 60 hp engine with these cylinders? Thanks for the help.