kordasn

Hello there people who browse the engine forum. I am wondering the significance of the temperature limit on a nitro engine, specifically the G3.0 by HPI, stock on the Firestorm, a RWD 1/10 buggy, stock engine, etc. The specific question is the hard temperature limit on the engine (from the manual) is 250, the goal is 190~230. It says that if the engine is above 250^ the engine gets damaged. Most people on RC forums suggest to 'tune for performance, not for temperature.' Generally what I am finding is that I should be running the engine leaner than what would be below 230^, if I were tuning it for performance.

Specifically when doing 'the pinch test,' I am finding that the engine revs slightly and turns off, as you'd expect. I can verify this belief by leaning out the engine, in which case the engine stalls quicker. If I richen it out, it will speed up much more then turn off (I would like to set it slightly rich in any case, but ignore that for the time being). More than likely, it's at VERY close to where it should be as far as tuning goes. However, when I measure the temperature after WOT it is above 250. I can richen it out a bit, but even still, the engine is really hot, main point: engine is hot. Also, it's clear that there is plenty of performance to be had from leaning it. The fuel is 20%/16% lube, I believe.

This has been how it has run since day 1 basically, which is not a negative thing there are no engine leaks and as far as I can tell, it's in pretty good working condition, maybe 3 gallons of fuel through it?

After that short wall of text, is there a problem with > 250^, if so how do I fix it, are you supposed to measure the temperature at WOT???

Let me know what you can, any advice with respect to tuning is going to be (edit: from needed to) appeciated.

twomanytoys

250 for any engine is not bad at all to anyones specs but the manufacture. Most engines dont really come alive unless its above 250. If you are running at 250 and it runs good with good smoke then dont worry about it. If you are running hard from doing drags and hill climbs and temps reach up to 280 dont worry. When it starts to get up to 300 mark is when you need to slow down or shut it off. Just remember to set your piston at BDC after every run and it will last for a long time. Dont worry about temps so much. Its a good guide to go by but all engines are different. You will drive yourself crazy if you tune by temps. Run it hard and get a good high base temp then leave it alone. High base temp meaning max temp you would run when running hard. Usually 280 is pretty safe for max running temp. 250-260 is about perfect.

NitroTherapist

You never see heli and plane guys using temp guns and they are running at high rpm's most of the time and they never have problems with a short engine life.
Man I wouldnt kill myself over trying to tune by temp.

kordasn

Thanks for the info guys!

slayerphonics

Honestly temps are just for refrence you can tune by temps but you'll never get the true power out of your engine.

If its got good smoke, and no lean bogs, let it run where its at. If its running 260 and smoke is coming out and its not lean bogging let it run there, some engines love 260 some love 220. Depends on the motor and the age of the motor.

I use my temp gun more when I first break in an engine, during the first gallon after that I've kinda learned how the motor acts and just check it every now and then.

Good luck