thinking of new prop

[tswiczko]

I apologise for not reading more on props before posting but I have an 1989 mach1 (mv2450)magnum 270 hp mercruiser. alpha one 1:50 and 14.25x22 3 blade prop. It is a dog out of the hole but runs 42 knotts (not mph) gps WOT about 4400 rpm. I was offered a 5 blade 21 pitch of same diameter at a fair price where would I see any change in performance.(both props are stainless) and would I see a change in my fuel consumption (boat weighs about 4300+ loaded)

 

[junior1113]

Re: thinking of new prop

3x22 to 5x21 rule of thumb drop 1" pitch for every aditional blade so u would prob. drop 100-150 wot rpms. better hole shots, fuel is going to be better on a five (not much)