All Max Engines come with novarossi carbs (its a novarossi based engine!!)
the new carbs are 2 needle carbs and are great. Ther is NO NEED to change the carb...NONE WHATSOEVER.
The .1mm shim should be added under the button head. Start with a 6F plug. You may even go colder if the tracks warrant it.
impalabob64 - these engines were designed for 16% nitro and if we increase the nitro content we need to increase the head clearance or risk detonation.