Originally Posted by racenut123
that seems like a lot of difference on the IR number between the 4000 and the 5000.I am glad I purchased the 5000.Am I looking at this wrong?
Originally Posted by Danny/SMC
It's normal for a smaller pack to have higher IR and lower average voltage. When it comes to Lipos the bigger the cells the better they tend to be. This is why it's important to have a maximum size rule like ROAR decided to do.
I had noticed the same thing as racenut but was assuming it had to do with cell size/capacity or some such which Danny's response seems to confirm.
My question would be this...Danny's answer describes using the maximum size (capacity) cells allowed, but the voltage increase proved fairly marginal in this case. The way I'd look at it (not necessarily the RIGHT way to look at it, mind you) would be that I would have gained 1/2 of 1% in voltage for an addition of a little over 3% increase in total vehicle weight (45g against the 1418g minimum for foam TC...slightly less percent if using the rubber TC weight). To me that seems a questionable trade-off if the additional mah capacity isn't needed. In fact for me it tipped the balance to the smaller capicity cells with their lighter weight.
Now, this certainly assumes a few things:
Firstly, and I'm WAY open to correction, while low IR is probably good it is higher voltage and/or longer run time where the "rubber meets the road" so to speak.
Secondly, that I DON'T need the additional 1000mah of capacity for 5 minute heats. If we end up increasing heat lengths this may or may not fall by the wayside.
Third, and possibly most important, there isn't already 45g of ballast being added to "make weight". In my particular case I am not, so that 45g "in hand" is significant.
These were the reasons I went with the 4000 packs. Curious if my reasoning stands or is invalid.