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oldboy
18-03-2013, 07:20 PM
Hi Guys And Gals

Even after a year and a half of racing i am still struggling to get my head around this, i am looking for some new lipo's for myself and my son without breaking the bank have looked at some of the cheaper batterys and notice that the C rating is lower normally about 30C. we both race touring cars with 13.5t motors mainly indoor but sometimes outdoor. could someone advise me what sort of C rating i should be using (or could get away with) also if anyone has any idea's which lipos are decent at a decent price that would be good (7.4v Stick brca legal would be good but possibly not vital)

Thanks very much Bob

SlowOne
22-03-2013, 06:46 PM
C rating is the number of times the capacity the cell can deliver. As a number, it is very misleading. To keep the numbers simple for me (!)...

A 4000mAh LiPo will deliver a steady four amps (1000mA in an amp) for an hour. If it 'says' 30C on the pack it will deliver 120A (30 x 4) for about two minutes before it goes flat. If it also 'says' 60C "burst" it will deliver 240A for about half a second.

However, and it is big "however", those numbers are generated by testing the cell under load, and it depends on what load is applied and down to what voltage, and how good the measuring equipment is. My experience is that the more reputable the makers name (SMC, Reedy, RevTech, Orion, etc.) the more likely the 'C' rating is to be delivered in real use.

If you are running 13.5T 'blinky' then something around 40C will be fine. If it is 13.5 'boosted' then try to find something around 60C. Whichever you choose, spend more to get more performance and life from the cell.

Most important is capacity. If running 13.5 then the more capacity you have the less voltage drop you get in the race and the faster the car will be over the last few laps. I don't run TC, so perhaps someone else can recommend a capacity level to suit this class. Sorry to say, you will get what you pay for. HTH :)

oldboy
23-03-2013, 10:44 PM
Thanks very much i think i am beginning to grasp it now:thumbsup: