Help ! Totally confused

[crusher]

I am on my first scratch build of a Cat 330b 1/14 scale. I am at the stage of buying a battery and charger, the more I search the net the more I am confused. I am looking at a Turnigy ultimate 7500mah 2s2p, 7.4 Lipo. I have four esc's. two for tracks, one for swing and one for pump motor. The pump motor is a 560kv 10 turn motor, with a 90amp brushless esc. A 7.4 volt lipo will give me pump rpm of 4144 with direct drive. Am I looking in the right direction or am I missing something?
Any help would be appreciated.
Thanks
Terry

[Lil Giants]

When your 2s lipo is fully charged the voltage will be 8.4v, pump will be running closer to 4700rpm... what pump are you using?

I bought another one of these chargers through this site last night. Lots of times I'm charging 2 or 3 batts at once, sometimes 4.

http://www.robotshop.com/ca/en/x4-ac-plus-4-port-ac-dc-plus-multi-charger.html

[crusher]

Thanks for your reply Lil Giants, I have the pump from rc4wd, don't know who makes it probably China. I can lower the pump speed through the radio channel.
Terry

[Jack3M]

I would try to get just a 2s, skip the 2p as they don't balance well. Go straight 2s. Turnigy has done me very well.

My preference for a charger is the I-Charger Duo. You can charge up to 10s per side of the charger, balance, monitor the impedence over time to be able to tell when a battery is going south.

They are expensive chargers, but many believe they are the best out there.

[crusher]

Thanks for the info Jack3M, it really helps to get suggestions from experienced builders.
Terry