I am needing to buy a good temperature gauge for nitro rcs. I have been looking at several models which include: O'Donnell TGX1, Duratrax Flashpoint, and Micro Temp MT-EXP.

Any opinions?

Thanks!

I have the Duratrax one, it is merely a toy. The most accurate temp sensor are teh automotive grade hand helds with laser pointer.

But to be very honest, the best temp sensor are your eyes, ears, and trigger finger.
You need to know what teh engine sounds like when it is running good, no blubbering, from running too lean, no gargling from running to lean, just a steady good toned-pitch
You need to be able to see the signs of a good tune as well. seeing how much smoke is being issued out of the stinger and knowing just how much smoke will definitely help you in determining if you are running too lean or too rich.
And finally, you need to now how well your RC pulls with your trigger finger. If it pulls strong and all the other cues are in good order, you know you have a great tune, not too rich, not too lean, but teh engine is running at its max performance

To help you have an idea of what a good tuned engine sounds like, watch these vids. No need for temps at all, totally based on empirical cues.
http://www.youtube.com/watch?v=prX0OeQLrbw
http://www.youtube.com/watch?v=4Nt5t...eature=related

I have the Flashpoint also, its accurate and the least expinsive one of all (that I know of)
Like SAVAGEJIM said...eyes,& ears are the most critical for tuning, but I still like to use it just to
know what my temps are runnin at.

what about if you want to use the heat cycle method for break-in?

I understand the eyes, ear, sight thing, but want the temperature gauge to double check everything, know temperature of engine in relation to environment, different fuels, and different setups.

I cannot agree more with the heat-cycling method. Best break-in method I have come across. As a matter of fact, I literally rip out the break-in instructions that come in the manual of my RCs, they all say to IDLE teh engine for break-in and teh engine does not wear in at teh correct operating temp diameters.

It's not bad to have a temp sensor, I still have that habit of temping my engine. When you temp your engine, dont let it alarm you if you see high temps.

Totally ignore the temp recommendations of your engine manual, they are stupid cold. That is page you can rip out of your manual, useless BS from the manufacturer.

For my small blocks, the manuals tend to say around 200-240 degrees F, but I have temped my engine at 270 degrees F, and all the other cue tell me it is running just right, so I keep on running it at its current needle settings.

For big blocks, totally ignore what teh manual says. 250degrees F is stupid cold, these engines will easily break 275 degrees F and push even 300 on a good tune, especially on a warm day.

Well, I really need to buy a temperature gauge soon. I have a new Revo 3.3 I need to break in, but want to be relatively perfect with this RC. The manual says 270 btw.

I am looking at the Duratrax Flashpoint, O'Donnell TGX-1, Pro Exotics PE-2, and onboard Traxxas unit (no real place to put on my Revo). Need to buy quick. Any opinions on these?

raytech hand held unit

At least Traxxas is being realistic. In reality, based on several factors, that engine running range could be like 250-290 degree F.
So, dont lock yourself at teh 270 degree number, be sure to always use the sound and signed cues as you primary tuning aid.