Best props to try before dropping big $

[Skyhead22]

18' rinker captiva approx 2500 pounds dry empty. 4.3 was the largest engine offered but it's been fitted with a 5.0/LX. Alpha one gen 2, 1.83 ratio drive.

A 21" prop puts me 400 rpm over engine max which is 4800. Local marine shop says with my setup I can easily handle even a 28" but no way to tell how it will react getting on plane without trying it. He only has a 25" demo I can try.

I want 2 props. 1 I can put on for a day of tubing and casual family cruising and 1 prop to throw on for maximam performance and speed when it's just me because I'm a speed enthusiast.

Does anyone have experience with a similar setup? Will it plane out no problem with a 26 or 28 pitch prop? Should I just stick with the 21 for casual boating even though at WOT it's 5200 rpm? I can throttle back to 4800rpm and still run 50mph gps.

Opinions wanted thank you!

 

[Maclin]

Try the 25. If your engine now can only hit 5200 then going to a 28 probably would end up overpropped. Going up in steps to a 23 and trying first would be good, but if there is a 25 ready why not try it and see what the top RPM your engine can achieve with that

 

[Starcraft5834]

the best overall prop IMO is a 4 blade prop. offers optimum thrust for water sports, you will lose maybe 1-3 mph top end tho.. if losing 1-3 mph top end is to much.. (would seem to me whether your going 50mph or 47 mph, offers little difference in the grand scheme of things), buy a 3 bade for days you want the etra 1-3 mph. If it were me with your set up, I'd buy one good SS 4 blade prop and be done with it. would keep "a beater" extra prop stowed away for emergency to get u in.

 

[SkiDad]

personally a 23 would be your best bet to keep your rpm around 4800 - it would be within 1-2 mph of the 25 as your not going to get a lot over low 50's. If you want aluminum try a Turning Point hustler. It was 2 mph faster than my other props.

 

[Skyhead22]

the best overall prop IMO is a 4 blade prop. offers optimum thrust for water sports, you will lose maybe 1-3 mph top end tho.. if losing 1-3 mph top end is to much.. (would seem to me whether your going 50mph or 47 mph, offers little difference in the grand scheme of things), buy a 3 bade for days you want the etra 1-3 mph. If it were me with your set up, I'd buy one good SS 4 blade prop and be done with it. would keep "a beater" extra prop stowed away for emergency to get u in.

I think I read that when you get a 4 blade you go up a pitch or two than what you would need in a 3 blade. Or is that backwards? Maybe you go down I think I read a 4 blade in the same size as a 3 will take away rpm.

 

[Skyhead22]

personally a 23 would be your best bet to keep your rpm around 4800 - it would be within 1-2 mph of the 25 as your not going to get a lot over low 50's. If you want aluminum try a Turning Point hustler. It was 2 mph faster than my other props.

I'm pretty much dead set on stainless. Doesn't have to be polished even, it's just the extra couple mph. I would really like to hit 60. Right now at 5200 I'm at 55gps. But I'm a sucker for WOT! Having to throttle back kills me, but I need to keep the engine safe. Marina owner told me 5200 is just fine for the engine just don't run it at extended periods wide open.

 

[jimmbo]

"Local marine shop says with my setup I can easily handle even a 28" Is he breathing thru the top of his head?

Adding two inches should bring you in line with 4800. You mention tubing. A lot of people swear by the mercury High Five. Me, I swear by Mercury's Enertia, it has great acceleration and very good top speed. A 22 would be about right

If you click on the picture it can get real big

 

[SkiDad]

if you are trying to dial in that last few mph i would contact Ken @ Prop Gods. He sells powertech props and can tell you exactly what you need. I still don't think you will hit 60 and you really don't want to, as things can get pretty hairy at that speed with a boat not designed for it IMHO.