RE: REVO 2.5R strange temps/performance...
Mine was the same all of the time. I played with it and played with it, it would run ok at ok temps if I ran it extremely rich, but I'd find it still overheating when I'd run it WOT for short periods. I tried resetting the needles to factory and retuning several times, with no luck. Then I saw a post in another thread on this forum where someone mentioned the HSN fixture. Then I remembered that one time when resetting it to factory settings I had the high speed needle fixture back out instead of the needle, so I tightened it back in. I didn't know that the Highspeed needle fixture is fed fuel through a hole that HAS to be lined up with the fuel hole on the fuel line nipple. So after taking off the HSN fixture all together and realigning the fitting over the housing with the fueal line, it fixed everything. For the past three days I have been running it out in hot weather in heavy grass at WOT for extended periods with rare temperature spikes in the 230-250 range, but pretty steady temps in the 215-220 range. I was really getting frustrated but fixing the alignment of that fixture fixed my problems. Now if I could just learn how to drive and quit hitting things at high speeds. I'm on my second steering servo, damn I need to learn to drive.
But my point was, have you checked the alignment of the HSN fixture? If not, you should.