5.0L MPI prop suggestions

[gmctodd]

I have a 200LS Crownline w/ 5.0L MPI 1.62 alpha 1 w/ MM Vengeance 21P SS prop. The motor now has 27 hours and should be broke in. Current performance with 3 on board and gas is 51-52 mph (speedo) and 4600rpm. Which is reached after 6-8 seconds of WOT Operating range is 4600-5000 rpm. With the current load (normal for us) I think I should be closer to the 5000 rpm range. I am considering a 4 blade SS prop like the turbo 2+2 or the MM Vensura. What effect will the fourth blade have on the rpm in the same pitch as the three? Any experience with these props? Suggestions for others?

Thanks
Todd

 

[QC]

Re: 5.0L MPI prop suggestions

Merc says subtract 100 RPM for 4 vs. 3 blade of the same pitch. A 4 blade 19 may be in your future . . .