Are you sure your supposed to be running 3 shims.? I think it was 2 with my Picco, and they're the same engines. I run 3 shims and im running 30%. Have you tested the engine for air-leaks.?

Take a look at this one, a coupla guys run them at the track,

http://www.amainhobbies.com/product_...ducts_id/22974