I was unaware that speed was an issue with the Savage, but if it were...the solutions are to either get a better engine or gear the current engine for more top end speed than the stock gearing.
The engines for the Savage are becoming more and more prolific in capability. The new Picco .26 OUTLAW is the latest addition to the fleet. There is a new RB Concepts engine out there that supposedly will smoke anything in the .21 class. I run the Ofna Hyper 21 8 port (when I complete the break in, I'll have a better idea of its capabilities...but I hear it smokes the Nitrostar 21BB that comes stock).
Gearing is a matter of proper spur gear and clutch bell combination to give more speed than torque, and there are a few links on how to accomplish that.
BTW the same logic applies to the T-Maxx.