I flew an archer III last yr and it was a bitch when it was hot......
After a few days i found the knack was to have....
Mixture rich
Throttle ICO
Crank and as soon as she fired throttle fully forward then reduced back to 12....
It was specific to that particular aeroplane but. if yr running out of ideas it may work for you...
Not an expert disclaimer....
luv
xxx
f