Join Date: Jul 2009
Location: Jefferson City, Missouri
Eagle Mike sells the 688 kit and his add says its a forged piston. It also says it was designed to be used when a 685 big bore needs redone. It may extend the life of your engine when used that way, although I have talked to people who have 90,000+ miles on their stock pistons so another kit is likely not necessary for most.
I have the 685 and have been been very happy with the performance improvment over stock. I have 18,000 on it with zero oil use or problems of any kind.