What's the right boat prop help

[RAP727]

2011 Bayliner 185 flight series F18 4.3 Mercruiser I need to know the correct prop size and pitch. I bought the boat the prop that was on there was made to pull a wakeboard he was supposed to have given me the original prop but never did at 25 miles an hour I'm pushing 5000 RPMs

 

[QBhoy]

Holy moly. She’s way way under propped eh. Is the rpm limiter sounding an alarm on the dash ? Must have been some size of a man on the wakeboard that required that prop to pull him up !
I’d start with a 19” or a 21” and go from there. What’s on her now ? Must be like a 15” 5 blade or similar ? If your rpm and speed are accurate ?
I know a 1900 regal with a 4.3 mpi of a friends ran well propped with a 19” tempest plus on her alpha. Just around the 4800-4900 rpm wot at just a little over 50 gps. You don’t want too much pitch on these 4.3 MPi (if she is). They don’t have much grunt low down usually. Hope that helps.

 

[Scott06]

2011 Bayliner 185 flight series F18 4.3 Mercruiser I need to know the correct prop size and pitch. I bought the boat the prop that was on there was made to pull a wakeboard he was supposed to have given me the original prop but never did at 25 miles an hour I'm pushing 5000 RPMs

Sounds like it has a high five prop on it Given speed and rpms . Q has you steered correctly 19 or 21” pitch start with a black max or similar to get your bearings then can step up to something better if you like. Really depends on what you want to use the boat for