Howdy,

Just wondering if it is normal for engine temperature to change over a longer run? Last night was checking in the warm up and then again when run had finished. During 5 minute qualifiers no real change between the two readings. Over the longer 15 minute final the second reading at the end of the race was 25 degrees higher then the warm up.

Thanks in advance
Andrew

It takes a while that the engine is really warmed up. I have a clear telemetry readout:
https://www.youtube.com/watch?v=cwkVENYaK-k

On the right in the graph and right under is the temperature readout. The engine was pre-heated to almost 80 degrees C as you can see on the digital meter. From running the 1st lap (1:20 Youtube time) it took 2 minutes before the temperature goes up beyond the 80 degrees C. At 4:20 I do a practise start where you can see a huge raise of the temperature when the car is standing still. That is where the cooling stops and all the heat will concentrate in the engine.

Thanks Roelof, When i say warm up the car had been running for a few minutes at full speed on track and I would check it as i refueled the car before the run started.

Andrew could also be lower fuel pressure as the tank empties, drop in air temp, or a dreaded air leak.

What telemetry is that and is it possible to add exhaust gas temperature readings?

Harry,

Thank you, will check for air leaks. If it was fuel pressure should it be the same at the end of a 5 minute run as the fuel load comes down?

Thanks
Andrew

That one is based on an old datalogger from www.conrad.com
You can read it all here:
http://www.rctech.net/forum/nitro-ro...mes-alive.html

With standard analogue inputs and adding formula's and I/O transfer tables for the right readout on the screen I can add any type of analogue sensor. So yes, exhaust temps are possible.

The fuel pressure doesn't change as the tank empties. The exhaust is capable of supplying more than enough hot gas to pressurize the tank faster than the carburetor can suck fuel out of the tank.