84.5mm or 3.327" (1,413cc) is not an exclusive to anyone or any company, they can be made from either JE, Wiseco ross, cp, arias or any other forged piston company that will make custom pistons, at JE and most other companies the minimum order is four pistons and the cost is about $ 125.00 per piston retail including pin fitting and pin locks, Bore friendly gas Nitrided rings and tool steel pins are extra.
Anymore questions regarding pistons you may want to consult with people that know what they are talking about and deal with pistons every day not just some people that act as a vulture on this and other websites to do nothing except comment about parts they sell.
Call all of the piston companies arias, mtc,Wiseco, cp, Je, Manley, Lunati, Diamond, ross, etc and get a feel for who has the most experience with HP and the bike you are building, even do a poll and ask people that have bought from these companies.
As others have said the 1,396 makes the best overall kit with regards to HP and longevity, some race only engines are 85mm in a stock block however they will succumb to blown head gaskets and other similar maladies in a street application in a very short time. Perhaps someone here that has built a large bore bike can post some of THERE OWN dyno-graphs to illustrate the hp potential and then they should be able to also offer you a guarantee as to how long you should expect with the engine build you have chosen if you were to purchase either parts or a complete engine build from them along with the recipe for what HP you should expect.
Good luck with your build whatever piston/engine builder combination you should choose, for a large cc Busa engine with either a stroker or non stroker I would see what Dave Owen, Lees, Carpenter racing or other builders can offer.
John
