Ordering prop, is this the right size?

[5150abf]

2018 F50 on a 16' aluminum V-hull.

Mounted the engine in the middle hole got 5800 rpm, have since moved it to the bottom hole, so all the way up, rpm, went to 6200+ and climbing when I backed off the throttle but still doesn't blow out.

I need to drop at least 500 rpm, currently running a 11x11 so I want a 13x11 now yes?

Enginespert at work told me every inch of pith drops 250rpm, is that correct?

 

[Sea Rider]

You need to sit engine at a height in which water flow at speed passes right under small upper splash plate, prop will achieve the best thrust in all water cond. From there check again max wot rpm run, report if possible. Any prop can gain 200 to 500 wot revs, depends on lots of factors such as deck weight, HP, trim, hull design.

Happy Boating

 

[99yam40]

Usually the 1st number is prop diameter and 2nd is pitch.
do not get a prop too big to clead the other parts on lower unit.

I have read each inch of pitch should give around 200 RPM change

 

[rejesterd]

I think it's best to contact the manufacturer of the hull. For reference, I have an F50 on a 16.5' aluminum deep V, and I use a 10-5/8X12 prop. If I go full throttle, it reaches 6200 rpm (with just me and my gear in the boat). Since I realized that, I never go full throttle. There's a soft rev limiter on the engine, but it won't totally prevent you from going past the redline. I could probably get a different prop that wouldn't allow it to ever go above 6000, but it's money I don't really need to spend imo. There's no risk of damage if I'm always watching the tachometer. If yours goes higher than 6200, then I would increase the pitch by 2.

 

[QBhoy]

All great advice above.
Before you think about props the thing needs to be set up right as mentioned in first response. Do you think it was cavitation and producing the high rpm ? If so your height is wrong.
All the above being well and it is set up right, you need to know what it’s getting wot really, within the reason of being silly. When you say it hit over 6000 and climbing...it might suggest you had more to go and maybe need to drop by more than 500rpm.
General advice is around 200 rpm per 1” of pitch I’m sure. That’s around what I’ve seen on average.
And yeah, as stated. The first number is the diameter and second the pitch usually.

 

[5150abf]

Running a 6'' set back, not a jack plate, which is why I can run it so high and no, it wasn't cavitating or blowing out even in turns and still peeing fine.

The rpms were climbing really slow not jumping up like it was over trimmed.

I started in the middle hole and kept going up till it blew out and it never did.

Middle hole ran 5800 at 29 mph, top hole was at 31 and climbing when it went over 6000

I work for a boat manufacturer so can get stuff at cost so a new aluminum prop is pretty cheap, should have a spare anyhow.