Engine Temp
#16
Tech Initiate
Joined: Jul 2012
Posts: 39
but the guy that tuned it, after i told him i was at sea level says "With the altitude being so different you will need to lean out the high speed needle since there is more oxygen in the air when you are at sea level"
i dunno? sounds like i have some playing to do tomorrow
#17
Even then what he said kinda doesnt make any sense lol. You want to keep the same ratio of a/f no matter your altitude.
The higher you go the leaner you need.
If you had a good tune at sea level and didnt change your settings and say you took a trip (higher in altitude) and ran your engine it will seem rich. But this would also be based on the same ambient temp and relative humidity.
Hope i didnt get too carried away lol.
#18
Tech Initiate
Joined: Jul 2012
Posts: 39
Now im no chemist, physicist or meteorologist, but i would think air is a homogenous mixture. Meaning oxygen is a fairly consistent 20% (roughly) of the makeup of "air". Im pretty certain oxygen content doesn't change, but the overall air density does.
Even then what he said kinda doesnt make any sense lol. You want to keep the same ratio of a/f no matter your altitude.
The higher you go the leaner you need.
If you had a good tune at sea level and didnt change your settings and say you took a trip (higher in altitude) and ran your engine it will seem rich. But this would also be based on the same ambient temp and relative humidity.
Hope i didnt get too carried away lol.
Even then what he said kinda doesnt make any sense lol. You want to keep the same ratio of a/f no matter your altitude.
The higher you go the leaner you need.
If you had a good tune at sea level and didnt change your settings and say you took a trip (higher in altitude) and ran your engine it will seem rich. But this would also be based on the same ambient temp and relative humidity.
Hope i didnt get too carried away lol.
#20
I think people get too bogged down in details regarding nitro engines - no wonder people think 'sod that' and go brushless! Lol.
RCtech has some of the best info on the Web, but let's hope that newbies to the world of nitro are not being put off by all this confusion.
Our nitro engines engines are miniature marvels but being small, sometimes they can be cranky. Please bear in mind that our IC 'nitro' engines have been around a very long time - since the 40's - long before radio control was even a thing. Long before people had infrared thermometers.
Whilst keeping an eye on engine temps is no bad thing, our engines' operating temperatures are affected by several things:
There is a zone where our engines will run perfectly, leaner will reduce lubrication, increase temperature and risk premature failure. Richer will increase lubrication and reduce temperature.
So observing the smoke trail from the exhaust is a really easy visual way of making sure our engines are safe. No smoke = bad.
The sound of an engine is another way of knowing if all is well.
Getting a temp gun gadget is purely as an additional aid to help you achieve a correctly tuned engine. We shouldn't ignore our senses just because we're chasing an entirely arbitrary number with a temp gun.
My engines have run at different temps throughout their lifetime. Some run cooler, others hotter. Whilst I own a temp gun, the tune I arrive at is never derived from a temperature. Rather, once the engine is tuned correctly, I record the running temperature for reference.
RCtech has some of the best info on the Web, but let's hope that newbies to the world of nitro are not being put off by all this confusion.
Our nitro engines engines are miniature marvels but being small, sometimes they can be cranky. Please bear in mind that our IC 'nitro' engines have been around a very long time - since the 40's - long before radio control was even a thing. Long before people had infrared thermometers.
Whilst keeping an eye on engine temps is no bad thing, our engines' operating temperatures are affected by several things:
- Ambient conditions ie the weather
- The load being placed on the engine
- Air flow
- Fuel choice ie nitro/oil content
- Choice of plug
- Tuning
There is a zone where our engines will run perfectly, leaner will reduce lubrication, increase temperature and risk premature failure. Richer will increase lubrication and reduce temperature.
So observing the smoke trail from the exhaust is a really easy visual way of making sure our engines are safe. No smoke = bad.
The sound of an engine is another way of knowing if all is well.
Getting a temp gun gadget is purely as an additional aid to help you achieve a correctly tuned engine. We shouldn't ignore our senses just because we're chasing an entirely arbitrary number with a temp gun.
My engines have run at different temps throughout their lifetime. Some run cooler, others hotter. Whilst I own a temp gun, the tune I arrive at is never derived from a temperature. Rather, once the engine is tuned correctly, I record the running temperature for reference.




