Quote:
Originally Posted by jackerbes
APC TE 13 X 8
3S = 4473 RPM, 10.42V, 11.90A, 124W, temp 66F 73F
4S = 5022 RPM, 14.95V, 14.75A, 221W, temp 74F to 86F
3S thrust estimate = 769g
4S thrust estimate = 979g

My 835 kv  80 g motor shows (not exactly same prop):
4585 rpm, 10.42V, 11.65A, 745 g at 90% throttle,
5038 rpm, 14.95V, 12.74, 899 g at 82% throttle,
Quote:
Originally Posted by jackerbes
GP SF 11 X 4.5
3S = 5245 RPM, 10.53V, 10.38A, 109W, temp 72F to 78F (115F post run peak)
4S = 5958 RPM, 15.19V, 12.44A, 189W, temp 76F to 92F (105F post run peak)
3S thrust estimate = 707g
4S thrust estimate = 933g

I have (APC 11x4.7SF):
5271 rpm, 10.53V, 10,76A, 712g at 93% throttle
6004 rpm, 15.19V, 12.73A, 924g at 86% throttle
Quote:
Originally Posted by jackerbes
GP SF 10 X 7
3S = 4543 RPM, 10.22V, 12.07A, 123W, temp 69F to 80F (89F post run peak)
4S = 5251 RPM, 14.99V, 14.16A, 212W, temp 73F to 95F (111F post run peak)
3S thrust estimate = 472g
4S thrust estimate = 635g

I have (APC 11x7SF):
4520 rpm, 10.22V, 12.21A, 673 g at 91% throttle,
5198 rpm, 14.99V, 14.89A, 890g at 85% throttle,
1 inch more in diameter to reach same load on motor !??
Quote:
Originally Posted by jackerbes
APC SF 10 X 4.7
3S = 5724 RPM, 10.56V, 8.77A, 93W, temp 71F to 73F (83F post run peak)
4S = 6563 RPM, 15.37V, 10.69A, 164W, temp 71F to 77F (89F post run peak)
3S thrust estimate = 584g
4S thrust estimate = 787g

I have (APC 10x4.7SF):
5736 rpm, 10.56V, 8.08A, 560g at 92% throttle,
6554 rpm, 15.37V, 9.45A, 732g at 84% throttle.
I really think it looks like your setup don't reach full throttle under load, might be due to the ESC ?!
Quite puzzling for sure !