Originally Posted by
VS_Rody
It is set for 16% nitro but you can use the engine up to 25% nitro.
Sincerely, Rody
sorry i should of said it this way its set for 16 using the shims or the button head is made different?
because its the same shims as i always had since i started using os with the black head for years since it first came out.....?
thanks