How much nitro

[derrick]

Hi all just got my first nitro, am only a begginer am using 12% optifuel. Using more or less nitro does it effect the temperature of the engine, I was told today that using a higher percent of nitro the engine will run cooler, is this right, i am using a os 50 hyper.
Del.

[GravityKills]

Hi all just got my first nitro, am only a begginer am using 12% optifuel. Using more or less nitro does it effect the temperature of the engine, I was told today that using a higher percent of nitro the engine will run cooler, is this right, i am using a os 50 hyper.
Del.

I'd expect it to run hotter on higher nitro percentage, everything else unchanged. But, you -should- open the needle a couple of clicks with higher nitro fuel.

[Steve]

Yes, more nitro will allow the engine to run cooler. More nitro requires a richer needle setting so there is simply more fuel and oil flowing through the engine.

However....

1) 12% is fine for learning. Why spend any extra cash on unnecessary nitro content? Just buy even more 12% and fly more.

2) Provided the engine isn't stupidly lean then it will be fine. Don't get hung up on the engine temperature. These are little engines that turn very fast indeed so of course they're going to get hot, and the clever little Japanese fellas who designed them have done all the sums that tell them that they can withstand the heat generated during normal flying.

If you're engine is fully run-in then your main needle should be about 1.25 turns out with 12% nitro fuel, or there abouts. If you're not sure, get a more experienced club mate to check out the settings for you.

[Andy from Sandy]

Regardless of how much nitro you use if the engine is leaned out too much it will get very hot and damge itself.

When the engine is tuned correctly again regardless of how much nitro it will get to the same temperature.

With the correct fuel to air mixture for the amount of nitro content the engine will run at the same temperature.

With more nitro in the fuel though the needle setting is not so critical for getting good power.

If an engine is tuned correctly for low nitro when higher nitro content is then used the engine will run lean and will need to be richened up some. Now because the mixture of fuel to air is increased the gas entering the combustion chamber is more dense and this has a greater cooling effect.