Using the Gordon Blair formula,and plugging in an ambient air temperature of 25 C,and 10.69",I come up with 8411 rpm and 6562 rpm.
You could be better off going for 5850 rpm and 7500 rpm,with a length of 11.988"

Any formula that doesn't account for air temperature is worthless,especially if they've been using it on car engines with under-bonnet temperatures of 100C or more.Your average intake temperature,between the carburettor and the valve,will be slightly less than ambient air temperature.