What hull and KV motor are you using? The M445 is kind of a go to limited prop as long as your KV's are 2000 or lower. I have had success cutting diameter down to 43mm or using a 642 or some of the 443 and 444's out there. ABC 1714 work well also. Doctor Props 643/3 another option. NAMBA CHAMPION PROPS (torgg.com)
Mic