FDR's - I used to run 7.0 - 7.5 in 10.5, and have only run 17.5 once on a large track.... ran 6.0 - 6.2 FDR

With timing that is.

17.5 - Start around 6000-7500rpm. Timing settings highish... so close to max with low motor timing. Play with punch and turbo delay to keep heat away and stop esc from spazzing out. But usualy punch run around 200rpm per degree

10.5 - Start around 9000rpm. Timing set about mid way.. low motor timing. Same as above for punch and turbo delay., probably a little less aggressive on the punch

Should be ably to play with that