Another prop question..! 2018 210

[Soul_surfer]

Hey guys,
sorry to start another prop topic but I didn’t had the respond I wanted after searching on other post.

my 2018 210 have OEM 1579 prop.
I’m running extra 600’s on rear, 500 bow bag 2/3 filled, 300 lead weight placed everywhere.

The most popular prop seems to be 1617 or 1433

i wanted to know if the prop can have an impact on the wave.
because it seems everybody is talking about fuel economy or performance to plane or top end.

but is changing the prop has any wakesurf wise improvement ?


thanks

[greggmck]

I had done several prop comparisons measuring RPM, Fuel burn and noise levels. These results were published in this forum. We are competitive surfers and found NO impact on wave quality from any prop change in diameter as well as pitch. All the best.

Sent from my SM-G965U using Tapatalk

[Soul_surfer]

Thank you very much!

thats what I was thinking about.
just wasnt sure

[swatguy]

While it might not exactly change the shape at surf speeds , it definitely changes how you need to weight the boat. I went from a 1579 to a 1617 and I can tell you I had to offset the prop torque with extra weight to keep the wakeboard wake , for me it transferred to my surf wave as well. Granted I am on the older hull , but that’s been pretty consistent on all my wake boats moving to an aggressive prop.

[Soul_surfer]

Interesting
It make sense tho prop is bigger move a bit more water so push it a bit more too
adding an extra weight to correct the prop rotation is pretty much obvious

BUT more prop rotation should add more push no? And maybe a cleaner wave maybe a bit bigger ?
maybe it’s just my imagination too lol
thanks

[greggmck]

Here is a summary of the measurements I performed comparing props for my 2018 G23. I shared these results with the engineers at ACME. I can't speak to how prop changes would affect other hulls. But I even measured the hull roll angle while surfing with a precision angle gauge over the transom. The roll angles were identical for both props. And this makes sense. Keep in mind that while greater diameter props will move a greater volume of water for each rotation, when the boat is adjusted to the same speed ANY prop must be exerting the same force on the water or the boat speed would change (F=MA). Since we surf at a constant speed of 11.3 MPH each prop we tested was exerting the same force on the boat at that time. The differences between various props will be changes to top speed, acceleration, fuel burn, and engine rpm (noise levels).

Boat 2018 G23 H6DI
Conditions: Sea level. Air temp: 73 degrees. Water temp: 68 degrees.
Four persons including driver: Two Adults, Two teenagers
Total people weight 550 lbs. – All sitting on surf side (except driver on Goofy).
Fuel – Full to 80% for all tests

Lead ballast – total 900lbs.
Port side: 400lbs middle seat, 200lbs bow.
Starboard side: 200lbs middle seat, 100lbs bow.

[swatguy]

I don’t dispute the numbers for your G Gregg , but you aren’t comparing apples to apples here. You’re talking about a 6000lb 102inch beam G23 with a 17/17.5 prop . The hull shape , prop shaft angle , overall weight, and beam of the G boat are nowhere near that of a 210. What happens with a G prop as opposed to a 21ft 210 weighing in at 4000lbs with 14inch diameter prop and only a 98 inch beam is not the same. Further more the wet running surfaces are no where near Identical so you can’t expect the same results.


I can 100 percent tell you different props can change the wake characteristics on many different boats. On the flip side some hulls don’t experience any change because the difference isn’t significant enough to overcome the variables needed. . Surf wakes are definitely the least effected. Mostly due to the fact people are running so much ballast it tends to negate the Torque factor and running angle difference. So you really don’t experience the prop torque issue too much. I can for sure tell you skiing with my 1617 is different than skiing with my 1579. If I don’t offset the torque a bit with weight the wake is significantly more lobsided. It’s needs less offset at wakeboard speeds , and it needs less at surf speeds. I did lots of testing with Acme back when I was a Ski Centurion Factory Rep, as we were rolling out new hulls every year. Certain hulls experience different changes when swapping props. Certain hulls are more prone to roll as well and need more weight adjustments to have clean wakes. In the surf realm a lot of those aspects are minimized due to the speed and the weight of ballast used. Case in point a 220 vs a 210. Swapping props on a 220 has more of an effect on wakes on the 220 due to the deeper v hull. Companies really have made huge hull advancements in this arena to keep the changes and shifts minimal on the wake sports side.


You mentioned F/MA . While that is the case, it’s not that simple because your rpm’s will vary on each prop at a fixed speed and the torque value will also change .
as

	=	torque
	=	radius
	=	force
	=	angle between F and the lever arm

D


While in your scenario the you state the force remains a constant.........The radius value is changing with each prop. That will give you a different amount of torque between props if force is kept constant. Clearly the G is such a massive boat it would take a high jump to really overcome that aspect, but as the boats get smaller and lighter the prop has more of an effect with regards to torque . I won’t dive into the 3 blade vs 4 blade wake comparisons , but there is a significant difference in the actual wakes produced by those on numerous wakeboats.

[greggmck]

I'm not comparing my results to anything. I even stated: ". I can't speak to how prop changes would affect other hulls." I simply posted the measurements from my experience.

Sent from my SM-G965U using Tapatalk