Buggy engine shims and Nitro
 

hi guys,
i know for .12 onroads engines the usual shims for 16% is 0.4mm, 25% is 0.5mm, etc...

how about .21 offroads engines? what's the usual shims for 16% and 25% nitro? :confused:

or nobody uses 16% for .21 offroads? :weird:

every head button is different, so you need to measure your deck height or the distance from the top of the piston to the button. Once you know this, the general rule is .007"-.008" per 10% Nitro. So for 30% ball park is .021"-.024". Many things affect what is optimal like altitude or specific application, but this will get you in the ball park. The actual thickness of the shims is pointless unless you are referencing a specific engine where you know what a given amount of shims gives you for deck height.