Total guess, but maybe 80mph? It's funny, people say 'yeh, but imma be doing on road, so higher voltage is ok'. Wrong. On roads have more grip and therefore put even more stress on the electronics, makes sense to me, though as I say, I'm speaking from inherited knowledge, I haven't tried anything like that myself yet.

I have an order on the way from Amain for the 2200 castle MMM combo for my truggy conversion, I plan to try some 6s craziness on that in the near future. Hope it comes soon.