RE: Balsa USA Bristol M1 conversion to electric - how to?
Hello,
The 4130 will work with a 15x8 prop on 6S, although I think it might be overkill. I have been flying a 6 lb aerobatic airplanes on the same motor using a 16x12 prop and a 5S battery. It depends on the weight: up to 7 lbs on 5S should be fine for "peppy scale flight". If heavier than that, then a 6S battery might be a better choice.
Good luck,
Teo