RE: Sequence of shimming vs nitro
Destroyed plug elements, pitted, sandblasted piston and head.
Out of control heat build up confused for simply being too lean.
Quickly hammered out con rods.
All this is considered good in many forms of motor sports if you are fully sponsored.
Nitro drag racers toss the pistons and all other heat exhausted parts after every run.
Decide what is right for you.