Yes you need to tell us what starter box you are using.
I'm running the Ofna truggy box with the twin 775 motors. I run a 4S 5000mah Lipo and it last a minimum of 2 whole race days. The only modification I made was to get rid of the Tamiya plug and change it to Deans. I also use a Lipo alarm buzzer so I don't over discharge the battery. Has not buzzed once yet. I've been running this setup for over 6 months without a single issue.