tuning in different temperatures

[gnarkill]

I found this article on tuning a nitro in different temperatures. I have never really looked into this but here it is:

Temperature
Hot weather requires a leaner mixture setting; cold weather requires a richer setting. Most people assume the opposite because they treat the mixture needle like a thermostat. It is wrong to assume that colder weather requires a leaner setting to keep heat in the engine and vice versa. Cold air is denser than hot air. The denser, colder air packs more oxygen into the engine, so going from hot weather to cold needs a commensurate increase of fuel to balance ratio of fuel-burning oxygen and the fuel itself. The opposite is true in hotter weather. Going from cold to hot weather requires a leaner mixture setting.

Like it said that most people assume the opposite, I did think otherwise of the article. Is this the truth?

This article was found at: http://www.rchobbies.org/cars_eng-tuning.htm

 

[Rolex]

Yes, that's the truth. It has to do with the oxygen concentration in the air.

 

[gnarkill]

Yes, that's the truth. It has to do with the oxygen concentration in the air.

Basically the one question that I have then is that when it is hot and humid do I richen or lean my motor because when leaned I notice that it bogs some, or sounds like it is borderline of flaming out. This is really something new to me so please bare with me.:\

 

[MotoGod]

Remember that tuning is all relative to your current tune. So if you have it tuned to run perfectly on a sunny 70 degree day and find yourself on a sunny 90 degree day, then you will have to lean it out a bit to get your perfect tune back. If you have it running too lean on a sunny 70 degree day, it may be perfect for a 90 degree sunny day and require no tuning.

Remember to tune in small increments and give the motor time to clear itself out before making more adjustments. 1/16th of a turn can be the difference between a perfect tune and one that runs like crap.... The more you tune, the better you will get to know YOUR motor.

 

[Rolex]

Just remember....you don't HAVE to retune just because the weather has changed, you only retune if the engine needs it.
Leaning it till it runs poorly is not the solution. Leave it where it runs good.
The whole point of this thread is to let you guys know WHY the engine ran great yesterday, and won't behave today.
If it runs fine, don't touch it!
Also remember, don't ever tune an engine that's cold. ALWAYS let it get up to running temp before changing any settings.

 

[MOPAR MESS]

I live in Michigan guys and it is so humid that my Motors flame out, run like crap and I just can't get that fine point. Do you suggest going back to original factory settings and tuning from there or should I rich in my mixture when it is humid out? I don't want to become a Nitro hater again. I used to be awesome at tuning but I want electric to race and now I am confused. Thanks a million! Mass

 

[mzanzirc]

I tuned my engine a while back.

If the weather changes and the car is really undriveable or crap, I'll look at touching the needles. Otherwise I will live with a hit in performance.

I'm not out here to win races, just to have fun.

 

[500 Mike]

I live in Michigan guys and it is so humid that my Motors flame out, run like crap and I just can't get that fine point. Do you suggest going back to original factory settings and tuning from there or should I rich in my mixture when it is humid out? I don't want to become a Nitro hater again. I used to be awesome at tuning but I want electric to race and now I am confused. Thanks a million! Mass

I agree with the original post at the top from 2009. Hot & humid weather will make it run rich so you should lean it out a bit. If the vehicle was running fine before the weather change, just lean it out a little at a time until it runs the way you expect.