what is the main difference then between the 13 x 13 and the 14 x 14 apart from the size I assume?
without sounding too thick, but what would change with this?
more upfront power? wake difference etc??
thanks for your reply though
and would this still be supplied by OJ, or can you recommend others and cheaper maybe?
What is your current prop size & pitch?
What is your boat model, year & engine?
The difference between 13x13 and 14x14 is the 13x13 will give you some neck snapping hole shot, but I suspect being so small it would also allow you to exceed the max engine RPM unless you kept an eye on it. Your top end wil lsuffer as well.
In a "perfect" world and no slippage on the prop, the pitch (second number) would equate to inches forward per revolution. So the x14 would move forwardx 14 inches per revolution, 13 is 13 inches... But it is not a perfect world...
The first number is Diameter. 13 seems a bit small, it will be easier to turn as there is not as much blade surface as the 14. Then there is cup, which is basically grip, more cup = more grip but also more power required to turn, less slippage and usually less vibration with higher pitch but you may want to research further if you are interested...
14.25x14OJ is what is being marketed as the "wakeboard" prop. On my boat is has great hole shot, decent top end and I am right at max rpm at WOT.
It really depends on how you use your boat and what is important to you. I prefer hole shot over top end, I hardly ever run WOT and when I do it is for quick bursts. When I cruise from point to point I usually run around 30-32MPH, any faster and it starts burning fuel too fast for my wants, besides, I'm in no hurry (usually) to get anywhere.
I would be interested, for myself, to try out an Acme 1433, but I really don't see the need as the OJ 14.25x14I have seems to work just fine.
The numbers are diameter x pitch. As you go up in diameter you usually have to go down in pitch so the prop is "flatter". The lower the pitch the faster the engine RPM's go up and the faster the boat will accelerate from still. The higher the pitch the slower it will plane but the faster it will be at the top end.
Any change in prop is a trade off. But, some props just work better on certain model boats. My stock prop was a 13.7 x 17.5, I think. It had a lot of top end but was pitched so high that the boat would not quite reach max RPM (although this can be a good thing). On the other hand, it would plane very slowly when loaded down.
I don't load a lot of ballast. I run a 750 in the rear and a 400 up front for surfing with about 8 people in the boat. I wanted a little more hole shot and did not want to give up any top end. The ACME 1161 is 13.5 x 16. It's perfect for my needs. In fact, I think Cab and Moombadaze also run this same prop. But, unlike a lot of others, my second choice would actually be my old stock prop, not the wakeboard prop. But, I absolutely understand why those who load a lot of ballast and want to run at 22 MPH want that prop.
At any rate, the thing to do is figure out what you like to do and then choose the best all around prop for your own application. One isn't better than another but it may be better for you.