Be more specific as to "how" it cuts out, sounds like your LSN is way out af adjustment. If the idle is normal, then slowly starts to drop, and you hear at sound sputtery, the LSN is too rich. If the engine starts and then the idle starts to rise and then it dies the LSN is set too lean. It will take some time for you to understand how to "listen" to the engine. Once you get an ear for how an engine in good clean tune sounds, it will be a breeze. Be patient, and most importantly adjust a little bit at a time on the carb needles.
Rich

One of the first things to hop up should be your diffs.
Add two more spider gears/kyosho mp7.5 bevel shafts and fill them with silicone diff oil.

Secondly would be to replace stock servo saver with an ofna monster pirate servo saver. Use an alum servo horn.


Great info on these and more can be found at
http://www.savage-central.com//ftopic10557.html

Alot of these hopups are inexpensive and effective.