Need better hole shot

[Frostz28]

Hey guys, been reading for a while but this is my first post. I have tried to my best to learn and understand the whole prop set up, but so many numbers start swirling that I just get overwhelmed. I've tried a several other options to help sort it out before posting yet another "what prop should I use" thread, but I just don't know what to do. I have a 2005 Rinker captiva 212. I we bought it two years ago and it has been great. Runs very well, and is a big up grade (size wise) from out old boat. The problem I have is It cannot seem to get up on plane fast enough. I don't expect it to be a race boat or anything like that. My family has always had boats, my grandparents, then my dad, and members of our extended family. I'm no expert by ANY means but I am familiar enough to know that this hole shot is unacceptable. Its not TERRIBLE with just 3-4 people on board. The problem comes in when I have 6 or more people OR I try to pull a tuber or skier. It takes FOREVER to get up on plane. I have to run people up to the front to try to get the nose down. It takes Far longer than any other boat I have ever been in. As for the boat, It has a 5.0 Mercruiser. I have not personally weighted it but research says it weighs 3050 pounds, I estimate I have on average between 1000 and 1500 pounds on board of gear and passengers depending on how many people are with. (not counting fuel, not sure what size the tank is) I know the speed and RPM's at WOT along with the prop dimensions are important information. Unfortunately I don't have that info right now. Last year I tried Multiple different prop set ups, and honestly I couldn't even tell you what ones we tried. I went to the local "prop guy" and he kept sending me with props to try, then I would come back and say "better" or "worse" and he would give me another to try. There were some minor improvements but still didn't come out of the hole right. We are getting ready to head back down to the lake for the first time this year next month and I would like to bring a prop with me to start the experiment with. I'm wondering if we just didn't take a big enough swing last year or something. I also know from my research that adding power to the 5.0 is pretty pointless endeavor. If I can't get this boat to come out of the hole good enough to pull skiiers and tubers I will start looking for a different boat, which won't break my heart, I just feel like I should be able to. I grew up skiing behind boats with much less horsepower. Is there a way with the limited information I've given that anyone could suggest a prop size that I could try, like a "if this doesn't work nothing will" kind of prop. I know I will lose top end and I know if there is the danger of over revving. At this point I just want to find out if I can prop it to get it out of the water. If I find one but it over revs or something I can start backing off a bit to see if I can find a happy medium but like I said if I just can't get it out of the water it might be time to start boat shopping. Sorry for another prop question I just don't know where to turn at this point. Thanks guys!

 

[racerone]

Step #1 is to have the drive tested on a dynamometer.----Test power output of the motor.----Step #2 is to have boat weighed.

 

[alldodge]

problem comes in when I have 6 or more people OR I try to pull a tuber or skier.

I went to the local "prop guy" and he kept sending me with props to try, then I would come back and say "better" or "worse" and he would give me another to try. There were some minor improvements but still didn't come out of the hole right.

This tells me most of the issue and changing props will not do much as you have found out. A 5.0 isn't much better then a 4.3, and what you need is more HP.

You could fix it with a 5.7 but not sure your willing to do that. Is the motor a carb or MPI?

 

[briangcc]

You're probably in the 260HP range with the Merc 5.0 IF its MPI....it was less if it was carb'd. That's what was listed in my FourWinns brochure when I ordered that boat with the Volvo 5.0 MPI - had 270HP.

My gut says you *might* be better served with a set of adjustable tabs on the transom to help you get up and out of the water if you're carrying a large load. That and possibly a 4 blade prop for watersports. Or just adjust who sits where....the MIL can sit on the dock

 

[Scott Danforth]

What is your WOT RPM when you are up on plane?

Carb or EFI?

What prop are you running?

Your fuel tank is 42 gallons, so just shy of 300#

 

[Scott Danforth]

Additional questions.

Gear ratio?

Do you always have 1000-1500 people on board?

If so, are they sitting in the bow or is everyone behind the windshield?

 

[airshot]

To much boat and people and not enough HP !! You might be able to help it some, but your not gonna fix it like you want without more HP.

 

[ejnichol]

Did you try the Michigan Wheel Vortex 4 blade AL 15 X 16 prop?

I have a VP 5.0 GXi 270 HP Chapparel 22foot+plat;(3600lbs empty) 5 adults 45 gal gas pull two skiers up no problem.

Something else wrong water logged, motor sick etc, if that prop won't move it..

 

[jimmbo]

A loaded 21 ft, is not going to be a Ball of Fire, with any engine less than a Big Block. Torque is what you need, not more high Rpm HP. In fact, increasing the top end HP, of any given Displacement, often results in poorer Holeshot

I have an 18.5 ft with a 5.7, it has decent but not outstanding Holeshot, compared to my Outboards

 

[Scott06]

Did you try the Michigan Wheel Vortex 4 blade AL 15 X 16 prop?

I have a VP 5.0 GXi 270 HP Chapparel 22foot+plat;(3600lbs empty) 5 adults 45 gal gas pull two skiers up no problem.

Something else wrong water logged, motor sick etc, if that prop won't move it..

I also had good luck on a previous boat that was underpowered With the Mich Vortex 4 blades. used a 16" for skiing and 18" for tubing and general cruise.

Hey guys, been reading for a while but this is my first post. I have tried to my best to learn and understand the whole prop set up, but so many numbers start swirling that I just get overwhelmed. I've tried a several other options to help sort it out before posting yet another "what prop should I use" thread, but I just don't know what to do. I have a 2005 Rinker captiva 212. I we bought it two years ago and it has been great. Runs very well, and is a big up grade (size wise) from out old boat. The problem I have is It cannot seem to get up on plane fast enough. I don't expect it to be a race boat or anything like that. My family has always had boats, my grandparents, then my dad, and members of our extended family. I'm no expert by ANY means but I am familiar enough to know that this hole shot is unacceptable. Its not TERRIBLE with just 3-4 people on board. The problem comes in when I have 6 or more people OR I try to pull a tuber or skier. It takes FOREVER to get up on plane. I have to run people up to the front to try to get the nose down. It takes Far longer than any other boat I have ever been in. As for the boat, It has a 5.0 Mercruiser. I have not personally weighted it but research says it weighs 3050 pounds, I estimate I have on average between 1000 and 1500 pounds on board of gear and passengers depending on how many people are with. (not counting fuel, not sure what size the tank is) I know the speed and RPM's at WOT along with the prop dimensions are important information. Unfortunately I don't have that info right now. Last year I tried Multiple different prop set ups, and honestly I couldn't even tell you what ones we tried. I went to the local "prop guy" and he kept sending me with props to try, then I would come back and say "better" or "worse" and he would give me another to try. There were some minor improvements but still didn't come out of the hole right. We are getting ready to head back down to the lake for the first time this year next month and I would like to bring a prop with me to start the experiment with. I'm wondering if we just didn't take a big enough swing last year or something. I also know from my research that adding power to the 5.0 is pretty pointless endeavor. If I can't get this boat to come out of the hole good enough to pull skiiers and tubers I will start looking for a different boat, which won't break my heart, I just feel like I should be able to. I grew up skiing behind boats with much less horsepower. Is there a way with the limited information I've given that anyone could suggest a prop size that I could try, like a "if this doesn't work nothing will" kind of prop. I know I will lose top end and I know if there is the danger of over revving. At this point I just want to find out if I can prop it to get it out of the water. If I find one but it over revs or something I can start backing off a bit to see if I can find a happy medium but like I said if I just can't get it out of the water it might be time to start boat shopping. Sorry for another prop question I just don't know where to turn at this point. Thanks guys!

to the OP- Its great you have a shop that will let you play with them. First makes sure the engine is in good shape tune up wise. As mentioned you will need weight up front. When there are 4 adults sitting across the back bench in my boat it drags some azz.

Determine your current prop style and pitch , and WOT rpm . Then select something down in pitch. I have used 4 blade props on my last two boats for this purpose. My primary use is skiing or boarding with 6-7 people in the boat ( 21 ft Sea Ray 200 sport 5.0 with Edlebrock carb approx 260 hp).

If the engine is in good shape a good 4 blade will help holeshot and give some stern lift. Yes a 5.7 would be better but I really get great holeshot when towing with a 5.0. I get best holeshot with a Vensura 4 blade, best overall Performance with a Revolution 4. The smaller less cupped blades of the vensura allow the engine to spin up better into its powerband , but has crazy slip at WOT. The Revolution 4 is almost too much to spin down low, but had like 12% slip at top end and can trim out more.

 

[Scott Danforth]

on my 19 foot searay with the 220 hp 2-barrel carbed V8. I had a 15", 19p stainless 3-blade. If I had 1000-1500# of people in the boat, there is no way it would pull a skier, much less get on plane without moving at least 500# to the bow and lowering the trim tabs a bit.

however with 600# of people. (Driver, spotter, next skier) it would do fine with the next skier in the bow with the same prop.

 

[Frostz28]

What is your WOT RPM when you are up on plane?

Carb or EFI?

What prop are you running?

Your fuel tank is 42 gallons, so just shy of 300#

It is an EFI engine. I can’t remember exactly because we tried two or three last summer. If I remember correctly the rpm’s were right at the recommended max of 5000 the MPH I cannot remember exactly but it was right around 46. If memory serves me correctly.

 

[Frostz28]

Additional questions.

Gear ratio?

Do you always have 1000-1500 people on board?

If so, are they sitting in the bow or is everyone behind the windshield?

I believe it’s 1.47 gear ratio. And I don’t always have that much weight but it’s also not uncommon. The weight distribution is balanced I try to keep the weight up front as much as possible but more than two adults in the bow gets a little cramped. The people on board are not all adults there’s usually two adults up front me and another behind the window and kids under 12 scattered about. lol

 

[Frostz28]

This tells me most of the issue and changing props will not do much as you have found out. A 5.0 isn't much better then a 4.3, and what you need is more HP.

You could fix it with a 5.7 but not sure your willing to do that. Is the motor a carb or MPI?

Yeah that’s kinda what I’m realizing

 

[Frostz28]

To much boat and people and not enough HP !! You might be able to help it some, but your not gonna fix it like you want without more HP.

Yeah kinda the conclusion I’m coming to. Which is somewhat unfortunate, on the other hand I do love boat shopping! lll

 

[Frostz28]

Did you try the Michigan Wheel Vortex 4 blade AL 15 X 16 prop?

I have a VP 5.0 GXi 270 HP Chapparel 22foot+plat;(3600lbs empty) 5 adults 45 gal gas pull two skiers up no problem.

Something else wrong water logged, motor sick etc, if that prop won't move it..

Not yet, but I now have one in my Amazon shopping cart! lol with that prop did you have any issues with over revving or anything? That set up all seems similar to what I’m dealing with.

 

[Frostz28]

A loaded 21 ft, is not going to be a Ball of Fire, with any engine less than a Big Block. Torque is what you need, not more high Rpm HP. In fact, increasing the top end HP, of any given Displacement, often results in poorer Holeshot

I have an 18.5 ft with a 5.7, it has decent but not outstanding Holeshot, compared to my Outboards

Yeah I don’t need more top end, I mean 60mph sounds fun but I’d rather be able to take the kids skiing.

 

[Frostz28]

I also had good luck on a previous boat that was underpowered With the Mich Vortex 4 blades. used a 16" for skiing and 18" for tubing and general cruise.


to the OP- Its great you have a shop that will let you play with them. First makes sure the engine is in good shape tune up wise. As mentioned you will need weight up front. When there are 4 adults sitting across the back bench in my boat it drags some azz.

Determine your current prop style and pitch , and WOT rpm . Then select something down in pitch. I have used 4 blade props on my last two boats for this purpose. My primary use is skiing or boarding with 6-7 people in the boat ( 21 ft Sea Ray 200 sport 5.0 with Edlebrock carb approx 260 hp).

If the engine is in good shape a good 4 blade will help holeshot and give some stern lift. Yes a 5.7 would be better but I really get great holeshot when towing with a 5.0. I get best holeshot with a Vensura 4 blade, best overall Performance with a Revolution 4. The smaller less cupped blades of the vensura allow the engine to spin up better into its powerband , but has crazy slip at WOT. The Revolution 4 is almost too much to spin down low, but had like 12% slip at top end and can trim out more.

That’s good to know. I was looking at the Revolution 4. Maybe I’ll grab a few 4 blade props and just play around with em.

 

[alldodge]

Good info, and since your not talking about full time loading IMO, the WOT is not relevant

Example: 23 ft, 454 and reached WOT using 21 pitch 3 blade
For pulling skiers with several onboard I changed to 19 pitch 3 blade and could over rev

Tired to pull up 12 skiers and knee boards at one time but 2 fell off so only got 10 up with 19P

Last note: keep in mind more blades decrease slip and what you need is more slip to get your RPM up higher faster to get motor into it's higer torque curve. Not saying that 4 blade will be better then 3 blade, just that everything plays and they are not just simple trades.

Also a 4 blade 19P = a 3 blade 21P, or the other way around if your reducing pitch/blades

 

[Scott Danforth]

I believe it’s 1.47 gear ratio.

1.47 is a bit steep for a 5.0

Should be 1.62:1