Higher nitro essentially lowers the flash point of the engine. there are some other chemistry definitions, but essentially that is what it does. The engine runs cooler. Go do all the research you want on that. I'm sure one of the experts can explain it better, but after running OS engine for most of the last 20 years...these are my findings. I also know that in SW texas last summer if I ran 20% nitro I had overheating problems on my YS 1.70DZ. When I switched back to 30% the problem went away. One recommendation you will hear often is in a cowled engine scenario you can run higher nitro to make the engine run cooler.

I'm not saying OS doesnt say to run higher nitro, i simply answered the guys question that the engine will run fine on higher nitro. Manufactures specs are often recommendations. Doesn't mean they wont work with other things. Many Futaba servos specifically say 4.8v only, but they will all comfortably run on a 6V system. I think if you use a high quality fuel you wont have problems. You are much more likely to have engine problems by running 10% nitro on a cheap fuel whose oils are not up to par.

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