Originally Posted by simonk
You'll know if you're reaching full throttle since it should happen rigth before the top of your stick movement, and going higher/trimming higher should have no effect. There is no possible way that resistance will have any effect, or the ESC would catch on fire. It can only be timing (which should only have a very small effect) or input voltage.
OK, the other possibility is that the motors are not all the same but I doubt that. I did check the throttle by going to 125% and, as you say, it makes no difference and I checked for voltage effects by changing batteries. I guess you'd know if it' could be timing on your firmware but the RCTigermotor T40A ESCs are on "high" timing because thay can stall the motors if they're lower.