I really apreciate all the advice. And the cautions! I was racing boats and I know exactly what you mean about sacrificing torque for rpm and the considerations of the airframe. We will be just playing. I don't plan on going full mod. I just wanted a ball park so I could stop short. You should have seen their faces when I showed them 4,000 rpm from a MACS pipe!
So, another question. We would run 40-60% nitro in the boats. Now these boats ran between 70-100 mph depending on the hull and engine size. Record speeds in some classes. Why don't plane guys run higher nitro?