I have a few vehicles that will do over 60. From what I've seen, the biggest limiting factor when pushing a truggy that fast is the tires. A 1515/2.5d on 6S lipo with gearing will get you to 60 pretty easily. The problem is controlling the truck. At 50, things really start to get hairy. At 60, things are down right scary. If you are going to go that fast regularly, I'd suggest very heavy shock fluid and heavy springs. For tires, I'd go with some GRPs. The Parks do very well for Monster Truck tires.

The best way to do it would be with a stiff suspension and GRP Rally tires, but you'll have to do a lot of gearing with the spur, pinion and front and rear diffs.

I've found that getting speed through sheer rpms is the worst way to do it, but that's just my opinion.