What mmm-neu motor setup woud get me 80mph topspeeds ? and 20min+ runtimes
Well, with a great battery you can go with a 1515/1Y 2200Kv, 1515/1.5D 2700Kv. Now if they fit go with 1521/1.5D 1900Kv or 1527/1D 2300Kv. Just get the best 30C lipos out there and go with 6S2P if possible. One question, why do you want to go 80MPH and still want 20MIN+ run time? You should go with one or the other.
I haven't seen them go for over 20min. though. You can make your DST go 60 or 70mph, but you won't get 20min. If you are planning on going 40mph+, then yes you could get over 20min. with 6S. I got over 20min. with my 1/8 buggy with 6S and my speeds were around 40mph.