Bought pistons for my b16 because I cracked a ringland. Was wondering how to clean the carbon off the new pistons without damaging the piston itself?

 

get some seafoam and a non wire brush

 

Take them to a shop and have them beadblasted, I did that to my CTR pistons and they looked 100% brand new. $5 a piston. Cleaning them is a betch, but I cleaned my old P61 pistons with a soft wire brush and lots of brake cleaner.

 

SeaFoam is your friend, but machine shop is the way.

 

i've read several places that bead blasting imbeds fragments in aluminum... maybe you just have to do it right..

i used a medium wire brush and parts cleaner then carb cleaner and a tooth brush for the fine stuff. no scoring or scratching anywhere. they were pretty gunked too.