RE: H9 Sundowner
"it didn't gain anything except hotter temps with 30% heli"
if you left the needle the same it would be lean when you move to higher nitro contet.
More nitro mean more o2... @ 30% nitro there is 66% more o2 in the cumbustion chamber. Thats why they call nitro liquid horse power.
good heli fuel also uses low viscosity oil because of the higher rpm heli engines 16000 and higher. But i would think any nitro engine would run better on high quality oil.