The 2 speed Jato tranny holds 0.8 spur gears, you can just get a 50t integy 0.8 steel spurgear and a Traxxas 24t clutchbell. Although I'm not sure the big block can hold that clutchbell? 🤔 worth a try though if you want to reach higher speeds with it. Or if you find another way let me know...
I think getting a bigger clutchbell instead spurgear may help with top end speed 👍 and I definitely had the wheelie issue as well, for that instead of a wheelie bar I just put 2.2" tires which made it so low its hard for it to pop, although every so often it does.
The 2.2" tires also help with...
I have a 2 speed nitro Rustler with a 3.3 as well except mine hits 65+mph, buy yourself a steel 50t spur gear from Here also get yourself a 24t clutch bell from Traxxas if mine goes 65 with the 3.3 if you put a big block I'm sure it will pass that forsure. Good luck 👍