Gortan,
RayJ is right, you will need to remove shims if running lower percentage nitro, other than 30%, I would suggest a total of .30mm shim, right now out of the box the engine had a total of .60mm shim=(3 x 20mm shims) you will need to remove 2 x .20mm shims and add 1 x .10mm shim = total of .30mm.