Currently running Cox motors with an AP .061 tossed in for fun. We are running either 18 or 20% Caster with 35% nitro. Sig or Wildcat are the two brands.

The 20% caster seems to leave things a little messier than the 18%. I have read numerous posts with widely varying opinions on the percentage of nitro to use.
We are at 6000 feet so therefore things work a little different here and perhaps this is why for regular sport flying I see lower percentage answers from everyone else in their similar posts.

Cox fuel worked fine back in the day. Does anyone have a figure on what the percentages were for it.

Thanks in advance for your advice.

Mark

Thanks Randy!