Colder plugs are needed.
At least one preferably two steps colder.
Exhaust is a must for any shot of NOS.
A cooler thermostat and some coolant additive, like Redline Water Wetter is a good idea as well.
An oil cooler is a good idea for anything over 65HP.
Stronger internals are a must for anything over 100HP.
I am by no means an expert.
Others will have more and perhaps better advice.
