if u want to go 81.5mm max..i suggest supercharge..if u want to go 82mm use this piston..cast iron but with strong material grade alloy C8a Grade, T-6 Heat treated for strength.
Highly resistant to heat. Australian made
What difrent between normal 13B engine and Cosmo Triple Rotor is't easy to instal to fd3s model and who have done it i saw at ah choi shop PDE 7007 how is't cost and how is't power goes?