gonsped

I noticed with the GS21R noob engine, the temperature of the engine increases as the fuel is used up in the fuel tank.

At the current setting - it starts (after running 2 tanks already - so the engine is warmed up) at the low 190F when the tank is full then goes as high as 250F just as the tank is about to run out of fuel.

Anyone else notice this with their engines? Race engine or not.

I'd assume that the engine ran rich at FULL fuel level as the *head* of the fuel liquid gives the engine that certain pressure. As the fuel is used up, the pressure head drops - causing the engine to run leaner - thus in effect - raising the temperature of the engine.

Comments?


NOTE: There is NO leak whatsoever on the fuel tubing (its new tubing) and all fuel inlet outlet from the tank to the engine and to the exhaust is snug.

nitro dipstick

I don't have a .21 engine at the present time but from my expereance nitro engines range from 240f to about 270f depending on the engine and the tuning. If your engine is tuned coeectly you should be running at about 220f after a one minute run. This should go up the longer the engine is run until you get up to about 250F to 270F. I have two .12 nova engines and they run at about 260 to 270F. You should tune for performance not temperature. If you are getting good power at the high and low end, I would not worry about it.

gonsped

What is the max. temp limit (in F) in their engine everyone tries to go below?

I read 270F should be as high as you want to go.

Ah10

your bottom end needle(idle fuel mixture adjustment) might be too lean. Meaning even when your high speed needle is rich enough but when you are off throttle you will be running lean and makes your motor running hotter and hotter!
Granted when you are out of fuel the engine temp will rise up but not that big of a gap, from 190 to 250.

On 0.21 size onroad motor you dont want to run it hotter then 210 on pratice day, 230 on race day! if you run it hotter expect the life of the engine will become shorter!

The Sleeper

Alittle more info would be helpful.

Are you filling your tank then starting the engine and just letting it idle? If so, then your low end needle is too lean.

Or, are you filling your tank then starting your engine and taking its' temperature before running your car around the track? If so, then you're not doing a good comparison between a full tank and a near empty tank.

afm

Also keep in mind that the longer the fuel pressure line coming out from the pipe, the leaner you can make your engine at mid range, so that fine tuning can also make the difference in temp. cahnges between full and low tank.
AFM

Rapid Roy

Having the temp gradually rise is a normal thing. If you look at Ron Paris' web site, he doesn't think that an engine is warmed up until the chassis is hot as well. This happens with the top racers when they flame out in the long mains.

popsracer

gonsped;

This is common in ALL Vehicles, but even more so in Trucks with large fuel tanks. A very long pressure line from the Pipe can also exacerbate the problem.

The solution is to tune your engine at about 1/2 a tank and fully warmed up (200 F). Also try making the pressure line to the tank a little shorter if possible.