Which MMM combo for my hb d8?

[SpEEdyBL]

Even though your not supposed to run the 2650 on 5s, i do. And really then, its only practical for speed runs. However it's never more than 10 degrees F warmer than on 4s no matter what. I've run it on both voltages on a track that is only 60 feet long, and a track with a 200 ft straight, and despite that it is geared for 50 mph on 5s (11 tooth pinon and its the smallest practical pinion gear you can use.), i still get about the same temps on both tracks. 150-160F for 5s and 140-150 on 4s. Honestly, unless you are just backyard bashing, you will get a lot more runtime and better laptimes with a 1700-1900 kv motor. Look into the tekin T8 motors which are similar to the neu and castle motors, but have more kv options.