I bought a used lrp sxx competition v2 esc and stock spec v2 esc off of ebay as well as a reedy Sonic 13.5 and lrp x20 17.5 motors. I paired the x20 and sxx comp. together and the stock spec and reedy Sonic together. I havnt tried the stock spec/Sonic combo in a vehicle yet. My comp./x20 combo how ever is acting funny. (This is all mounted in my brand new T5m.) My set up is as follows:
battery - gens ace 4600 mah 60c 2s shorty
Esc - lrp sxx competition v2 with original capacitor
Motor - lrp x20 17.5T
Servo - savox 1258TG
Receiver - losi 2.4ghz dsm rtr radio (waiting on 4pls)
Glitch buster - racers edge
Everything powers up as it should, I calibrated the esc, everything works. Before the glitch buster, if I twitched the servo too fast it would kill power to everything. Like if I bang the wheel back and forth, everything shuts off. If I flip the on/off switch, everything comes back. Now with the glitch buster installed, everything works until I hammer the throttle. Then same thing. Everything dies. I don't have access to the lrp software. Any thoughts?

You did connect the sensor cable?
You also connected the 3 motor wires correctly? (A to A, B to B and C to C)

If so, try to disconnect the servo. Savox is known to cause some issues on weak BEC's

Everything is connected properly, I triple check that stuff lol I will try unplugging the servo tonight. I really hope it's not the servo, I love my 1258tg.

the bec on the ltp esc is not strong enough to run that savox.. you will need a good ubec.. or another servo

I was hoping it wouldn't come to that. I did fully recharge the battery, (it was at 7.6v, still more than enough) and it went away for now. But if it is indeed overstressing the Bec, I won't keep running it. I'm probably just going to swap servos to save weight instead of running an external bec until I can get my hands on a tekin rs pro which is the esc I originally wanted.