New advise on a new prop - Not a typical setup - NEW repowered boat

[Lost in Translation]

Hey just looking for some advise from the wise Boat gods. I have a 1986 Four Winns Freedom 160. It had a 3.0L V4 in it that had a cracked block so I repowered it to a 4.3L OMC V6. The 4.3L has a 15 x 19 prop on it currently and at WOT it is at 5200 RPMs. The motor should be 4200-4600 RPM WOT. So the big questions is should I go with a 15 x 23 to get it to drop down.... going 4 should drop it 400-600 RPM correct??? Thanks for any advise just want to make sure I get the right one the first time.

 

[jimmbo]

4" inches will be more like 600 - 800 rpm. A 23 would be a fair choice for a start,

 

[Lost in Translation]

4" inches will be more like 600 - 800 rpm. A 23 would be a fair choice for a start,

Thanks Jimmbo I figured this would be the best bet. I just bought a Michagen Match Vortex 14 x 23 with a hub kit. Once I will report how it reacted to it.

 

[Shaun_300]

Yup the 23 should put it right where it's supposed to be, 4500ish WOT. Let us know how it works out!

 

[Sea Rider]

How loaded was combo when achieved max 5100 wot rpm with a 15 x 19 prop ? Just for the record, would be interesting to repeat same test with new 14 x 23 prop to check how much wot rpm engine has reduced with + 4 pitch sizes ?

Happy Boating