We repowered from the original 250HP OX66 to the twin F150s in October 2005. We now have over 1000 hrs on them.
The props that were put on with the F150s were the ones recommended at that time. The 13.75" x 17" Black Stainless Steel props. They are not bad, overall, and certainly were correct in allowing the engines to reach the correct WOT RPM. However, we run 'heavy' a lot, on long offshore trips to the Norfolk Canyon, and the props would ventilate far too much when running in a following sea, and would lose bite when punching into a steep head sea.
After a few years of that, I did some experimenting - with the assistance of a great local prop shop - trying several different combinations of props. Eventually decided on a set of PowerTech props with the cushion-lock hub, in 15.25" x 16". The larger diameter greatly improved the bite in all conditions, but did have to drop one inch in pitch to keep the WOT RPMs where I wanted them. These props have been excellent overall, with the same cruising speed and about 1.5kts lower top speed.
The prop shop ran the old Black SS props through their new polishing machine, and they came out pretty nice. They're on a shelf in the garage, in case I ever need to swap them out.
The Reliance props were, I believe, just becoming available when we did all the experimenting. The prop shop had no experience with them, so we skipped them.
Many folks say that the 15.25" props are too much for the F150s, and cause clunking in the lower unit gear case. The PT props don't exhibit that, due to the cushion lock hubs.
Feel free to contact me by PM if you want to discuss this further on the phone.
Brian
