E550 6-8-10 lipo

[helistef]

Good morging,

I'm flying a E550 (heavy sports flying/soft 3D). I'm using 6 cells aplus lipo's 5300 Mah 22C. These give me 6 minutes of fun at 2100 rpm's.
My question is, what is the difference in flight times and performance if I use 8 cell's 3300 Mah (2x4 cell's 3300 Mah in series) ?
Or 10 cell's 3300 Mah (2x5 cell's 3300 Mah in series) ?
Can this be calculated?
Do I need an other ESC and motor, I'm using the standard for the E550.

Thanks...

[stevehonn]

You're not going to be able to use the motor or ESC for setups over 6S, the ESC is max 6S only and you can't get a small enough pinion to give a sane headspeed with the stock motor, the esiest alternative would be the motor and ESC for the E620 which is intended for higher voltage setups plus 600mm blades and the E620 tailboom & belt would be better to cope with the higher power output.

I've no experience with duration of these higher voltage setups and I'm sure someone else would be able to help but looking at the 8S 3300mAh setup, this has less overall charge so I'd guess flight times would be shorter, the 10S setup has more overall charge so assuming you fly the same and don't use the extra power flight times might increase, but could you resist the extra power!

[ama outlaw]

I'm sure there is a formula that explains to the ratio of Volts used to the mAh used as you change the voltage but keep watts the same. I just don't know what it is. However, I do know of this cool page that will figure it out for you. Just remember that as volts go up, amps go down (and so does Amp/hours of battery used). http://dhrc.rchomepage.com/calcAdvanced.htm

If you use an 800-900kV motor like the Z30A-800 then you will have headspeed where you want it on 8 cells and an 11T pinion.

[ghtracey]

P=IV is the relationship. Watts = Volts x Amps