2002 Sunscape 21 LSV Too Much Weight?

[sledandski]

So thanks to some advice from the crew and MalibuNation letting me take a ride in his boat, the wife and I pulled the trigger on a 2002 Sunscape 21 LSV a few weeks ago instead of waiting until next year. So far we are loving the boat but last night I ran into an interesting problem.

We went out with some friends last night to wakeboard and wanted to really load the boat up to throw a decent way. So we did some weight experimenting. Following was the load that was in the boat.

7 people with an average weight of about 155lbs per person so (1085lbs).

Full tank of fuel

Wedge down

Stock balast system full. The has the Malibu MLS system in it which has hard tanks in each of the rear lockers and then a soft tank in the ski locker. I have heard that the hard tanks are 250lbs each and I am guessing by the size that the ski locker bag it is around 450lbs (if anyone knows the spec on this I would be curious to know what it is).

Then I put 2 additional 450's in the back of the boat next to the hard tanks. They were not 100% full but I would guess about 400lbs each for a total of about 650lbs on each side.

We took off to see what the wake looked like and could not get over 14mph!! We were just barely on plane but could not get over that hump before the boat really planes out. We had 1-2 people in the bow and move another one up there and with this we just barely got up over the hump. Once we were past the 14mph mark we were fine, but getting over that hump took a long time. We ended up pulling the wedge up and the boat got up on plane fine then (it was still work but it did it fine).

So is there something I am missing?? The boat runs 46mph with three people on a GPS and motor seems strong (Monsoon 325) so I don't think I am making sub-par power. I have read on the forum where people are running 750lb and even 1100lb sacs in each locker so I do not think my weight is way out of wack. Is there something I totally missed?? Maybe a bow sac, different prop, few mermaids to help push?? It was just surprised when the boat did not have enough steam to pull this.

Thanks and the forum is awesome!! Glad I can now participate with a bu

[grandude]

You need to re prop to run that much weight. you likely have a 13.5 X 17.5 or 16. You should consider going to a Acme 1235 which is a 14.5X14.25. This will wake it right up.

[MalibuNation]

to what grandude says.

Congratulations!!

Where did you find the boat? Just got off the lake and going into the NW wind was chilly.

[sledandski]

You need to re prop to run that much weight. you likely have a 13.5 X 17.5 or 16. You should consider going to a Acme 1235 which is a 14.5X14.25. This will wake it right up.

to what grandude says.

Congratulations!!

Where did you find the boat? Just got off the lake and going into the NW wind was chilly.

You need to re prop to run that much weight. you likely have a 13.5 X 17.5 or 16. You should consider going to a Acme 1235 which is a 14.5X14.25. This will wake it right up.

MalibuNation

Boat actually came out of Iowa and I bought it from a dealer about 40min north of Chicago (Munson's Ski and Marine) We brought it back to Kzoo late Wednesday and got to play on it the first time Memorial day weekend. We were on Austin lake last night playing around.

grandude

So in regards to the prop. I am not sure what is on there (I am guessing whatever came with the boat, I will verify this when I am at the boat this weekend along with RPM at WOT). I do some barefooting and some slalom skiing (about 30% of my usage). So I need a prop that can run into the low 40's (I would like to be able to pull a solid 43ish), but will pull harder when sac'd out. Any thoughts on how well the Acme 1235 will do on the top end??

Thanks for the advice.

[WakeGirl]

Guessing, but it sounds like you've got an Acme 381 on there now. OJ 468 or 475 will do the trick.

[alxmlr789]

I don't know much about V drive props, but when I put 2800lbs on my Monsoon, i had to reprop as well. I have a SSLX, and even with the upgraded 525, I needed a new prop, badly. I went to the extreme with the 925, but I don't do any skiing or barefooting. I haven't taken the boat over 30 mph.

http://www.wakeprops.com/wakeboard-boat-propeller-finder/malibu-wakeboard-boat-propellers

^^ this link is what I based my decision off of.

Take a look, they are pretty spot on. My local dealer didn't really guide me in the right direction.

[MalibuNation]

I know you're a footer too ... keep us posted what you end up with. You might need 2 props.

[85 Barefoot]

Dude thats 2800#s of ballast with wedge and if you're hitting 46, likely the steepest Vdrive prop available. If you have to be getting low 40s you're aksing a lot of that boat if you also want to run that much weight. I'd call ACME for perhaps a more "non-standard" recommendation. Running almost 3k in weight AND needing to hit 40s is definitely not a common "blend". Good luck but just know you don't need near that much weight to get a "decent" wake.

[nyryan2001]

Sled- can you tolerate a 35-37mph wide open speed?

Slap an ACME 2315 on there and you can likely add more weight up to 22mph. If you wanna go extreme, thats how you get there.

The only other thing I would pass along is watch your prop shaft angle. Too much weight in the rear points the prop too far down and you loose too much thrust lifting the boat up vs pushing forward.

1. Re-prop the boat

2. Watch your prop shaft angle, if you get stuck, move more weight forward.... but not so much that you have the bow so low that you take rollers over the bow.

[Nitrousbird]

Re-prop for sure; you most likely have an Acme 381.

If you want to retain some form of top speed, the Acme 1939 would be a good answer. 1235 will kill your top speed; 1273 would be better but still probably not as much top end as you need

Downside is the 1939 isn't going to pull like the 1235/1273/2315 (not sure if there is enough hull clearance for the 2315).

1939 is more than enough prop for more weight than that on my boat (same hull)...but we are talking a 50HP and 600RPM difference in motors.

[UWSkier]

That's quite a bit of weight in the rear without bow ballast to balance it out. If this is a setup you plan on running regularly, prop down and add some weight in the nose.

If you're a barefooter or slalom skier too, I'd say make an incremental change and go to the 537. Propping down much further than that is going to increase drag, decrease speed, and likely require WOT for barefooting. You're also going to change wake characteristics going to a larger prop. The slalom and barefoot wakes on that boat with the 381 or 537 are phenomenal for a v drive.

Some say the 1939 and 537 are pretty much interchangeable, but it's been my experience that when you increase surface area, you typically lose a bit of speed. I haven't tested them myself though so I'd be making a call to Bill at Acme to discuss.

Edited June 3, 2013 by UWSkier

[sledandski]

Wow, thanks all for the feedback, This forum is awesome and I will definitely post what I end up with and how it works. It might be a few weeks as I also need to buy a boom and and a few other things and the wife is not letting me overspend my "toy" budget

Couple of responses to this great info:

1. I do need to be able to barefoot and slalom and preferably without changing props (this is a last resort). I can give up a few mph on the top end but I would like to be able to run a solid 43mph (usually barefoot around 40 long line, 42-43 if were dong 1-footers, sometimes we pull 2 footers at once).

2. The comments about the prop angle and too much weight in the back I think may be right on as part of the factor on this. On our first try I had about 250lbs of our roughly 1100lbs of people in the bow. I moved another buddy up there to make it closer to 450lbs and then the boat got up on plane. The boat really threw its nose up in the air when taking off, once up on plane(after moving the buddy) it was fine. I noticed that the bow seemed higher than normal and we were not anywhere near taking water on.

3. I have heard that 3 blade props are faster, maybe that would give some more low end power and help out on the top end??

As far as the weight that I run, I am still working on figuring this out (any advice is appreciated here also). With my old boat (89' american skier, advance) we usually ran about 1000lbs in the back and put people up front. The issue we ran into however was that at about 20mph the wake really started to disappear. As a result most of our boarding was done in the 18-20mph range. I realize this is slow and when we were playing around on Saturday I bumped up the speed to 21 and the wake stayed the same size. So with this boat I need to re-learn how the wake behaves at different speeds. Any recommendations on how people are weighting with this hull and speeds??

For surfing we ran the ski locker sac full, port side hard tank full, and then both 400lb fat sacs full (one in the rear next to the hard tank, one under the seat on the port side), starboard hard tank empty. This seems to work out great. My plan for wake boarding was to move the sac that was under the seat to the starboard locker and then fill up the hard tank and drop the wedge. This was the setup though that would not get up on plane until we moved another buddy up front.

Thanks again everyone for all the input, I am going to be on a lake with the inlaws for three days this weekend and will have a bit of time to try some things out

[UWSkier]

You won't find a 3 blade prop that fits a V drive with its 1.5:1 reduction. It's 4 blade or bust on that, and really, surface area is why you want a 4 blade with the V drive application. The more surface area you have on the prop, the better the speed holding and torque transfer will be.

If you're pulling multiple footers and doing lots of one-footers, it sounds to me like you might be best off leaving the 381 on and not running so much stern weight when you board. With the wedge, stock hard tanks, and the engine back there, you really don't need a ton of additional rear ballast to throw a respectable recreational wakeboarding wake. A 500 lb bag in the bow really reduces some of the peaky-ness of the wake too.

I've had 4 footers behind ours before. Average weight was 180 lbs. Had no problem holding 41 MPH with two of the guys throwing one-footers with the 381. Still had a bit of throttle left, but I doubt it would have gone more than 1-2 MPH faster. Same Monsoon as the '02.

EDIT: As for wake surfing, you need the wedge down with this hull. Fill your port hard tank, throw your 450 lb bag in there. Put the other bag under the port seat as full as you can and as far forward as you can. Bow ballast helps make the wake longer. With the exact same hull, I run 600 lbs in locker, 500ish under port seats, 500 in bow, wedge down. No center ballast. Works great.

Edited June 4, 2013 by UWSkier

[sledandski]

You won't find a 3 blade prop that fits a V drive with its 1.5:1 reduction. It's 4 blade or bust on that, and really, surface area is why you want a 4 blade with the V drive application. The more surface area you have on the prop, the better the speed holding and torque transfer will be.

If you're pulling multiple footers and doing lots of one-footers, it sounds to me like you might be best off leaving the 381 on and not running so much stern weight when you board. With the wedge, stock hard tanks, and the engine back there, you really don't need a ton of additional rear ballast to throw a respectable recreational wakeboarding wake. A 500 lb bag in the bow really reduces some of the peaky-ness of the wake too.

I've had 4 footers behind ours before. Average weight was 180 lbs. Had no problem holding 41 MPH with two of the guys throwing one-footers with the 381. Still had a bit of throttle left, but I doubt it would have gone more than 1-2 MPH faster. Same Monsoon as the '02.

EDIT: As for wake surfing, you need the wedge down with this hull. Fill your port hard tank, throw your 450 lb bag in there. Put the other bag under the port seat as full as you can and as far forward as you can. Bow ballast helps make the wake longer. With the exact same hull, I run 600 lbs in locker, 500ish under port seats, 500 in bow, wedge down. No center ballast. Works great.

UWskier,

Thanks for the input. I have a few other fat sac's and thought I would try your setup this weekend. In addition to my 2, 450lbs bags, I also have a 750 and a 400. Where are you putting the bow ballast (on the seat, under one of the seats, in the center)? Also, any reason to use the bow ballast instead of the ski locker? Seems like the weight and placement would be similar.

Thanks

[85 Barefoot]

You won't find a 3 blade prop that fits a V drive with its 1.5:1 reduction. It's 4 blade or bust on that, and really, surface area is why you want a 4 blade with the V drive application. The more surface area you have on the prop, the better the speed holding and torque transfer will be.

If you're pulling multiple footers and doing lots of one-footers, it sounds to me like you might be best off leaving the 381 on and not running so much stern weight when you board. With the wedge, stock hard tanks, and the engine back there, you really don't need a ton of additional rear ballast to throw a respectable recreational wakeboarding wake. A 500 lb bag in the bow really reduces some of the peaky-ness of the wake too.

I've had 4 footers behind ours before. Average weight was 180 lbs. Had no problem holding 41 MPH with two of the guys throwing one-footers with the 381. Still had a bit of throttle left, but I doubt it would have gone more than 1-2 MPH faster. Same Monsoon as the '02.

EDIT: As for wake surfing, you need the wedge down with this hull. Fill your port hard tank, throw your 450 lb bag in there. Put the other bag under the port seat as full as you can and as far forward as you can. Bow ballast helps make the wake longer. With the exact same hull, I run 600 lbs in locker, 500ish under port seats, 500 in bow, wedge down. No center ballast. Works great.

Actually there are 3 blades available that are comparable sizes and pitches to the wake props being suggested but given the weight OP wants to run, probably not a good option. a 4 blade on a massively weighted boat is like adding 4 wheel drive to a pickup truck.

[UWSkier]

UWskier,

Thanks for the input. I have a few other fat sac's and thought I would try your setup this weekend. In addition to my 2, 450lbs bags, I also have a 750 and a 400. Where are you putting the bow ballast (on the seat, under one of the seats, in the center)? Also, any reason to use the bow ballast instead of the ski locker? Seems like the weight and placement would be similar.

Thanks

For surfing, I run the bow ballast on whichever side we're surfing. For wakeboarding I put in the filler cushion and run it the wide way across the bow seats, but I don't have any ski locker ballast.

[sledandski]

You won't find a 3 blade prop that fits a V drive with its 1.5:1 reduction. It's 4 blade or bust on that, and really, surface area is why you want a 4 blade with the V drive application. The more surface area you have on the prop, the better the speed holding and torque transfer will be.

If you're pulling multiple footers and doing lots of one-footers, it sounds to me like you might be best off leaving the 381 on and not running so much stern weight when you board. With the wedge, stock hard tanks, and the engine back there, you really don't need a ton of additional rear ballast to throw a respectable recreational wakeboarding wake. A 500 lb bag in the bow really reduces some of the peaky-ness of the wake too.

I've had 4 footers behind ours before. Average weight was 180 lbs. Had no problem holding 41 MPH with two of the guys throwing one-footers with the 381. Still had a bit of throttle left, but I doubt it would have gone more than 1-2 MPH faster. Same Monsoon as the '02.

EDIT: As for wake surfing, you need the wedge down with this hull. Fill your port hard tank, throw your 450 lb bag in there. Put the other bag under the port seat as full as you can and as far forward as you can. Bow ballast helps make the wake longer. With the exact same hull, I run 600 lbs in locker, 500ish under port seats, 500 in bow, wedge down. No center ballast. Works great.

UWskier,

I ran you setup today for surfing and it worked great. The pocket was much longer than what it was before which was much nicer. Thanks again for the input!! I also tried running the setup with locker ballast instead of bow ballast and it was not quite as good.

Thanks again!!

[UWSkier]

Glad to hear it worked! These diamond-hull boats especially need weight in the bow for surfing. If you add stern weight, add some in the bow to counteract.

[sledandski]

Oh, one other thing to add. I have a 381 prop on there right now (13.5 x 17).

[greg2vlx]

Another prop would help, but if I understood your weight set up correctly you may need some more weight up front.

[UWSkier]

Oh, one other thing to add. I have a 381 prop on there right now (13.5 x 17).

381 is fine for surfing as long as you're not obscene with ballast. With my setup, you can comfortably run 2100-2300 RPM on the tach for best wake. Motor plods along just fine. Doesn't even feel like it's lugged down.

[sledandski]

I took and ran the boat at WOT this weekend with just me and the wife in it and about 1/3 tank of fuel just to see how things topped out. RPM on the timing gun was 4910 (perfect pass was 4940) and speed was 45mph (4-6" chop) all at WOT. The spec for WOT on this motor is 4800-5200 if I recall correctly. I might still give ACME a call and see about running a 537 prop. If I lose 1-2mph on the top end and gain 100-200rpm it might be a good trade, especially if it means some better performance at the low end.

[85 Barefoot]

Oh, one other thing to add. I have a 381 prop on there right now (13.5 x 17).

The 381 is actually a 17.5 pitch and the 537 will be a 16. If you're under 5000 RPM and throwing in that much weight, 537 might be a great fit for you but is still on the steeper side of modern props. You might even gain some top end actually as the pitch difference is almost 10%.

Edited June 10, 2013 by 85 Barefoot

[WakeGirl]

Just get the 537 & use the 381 as a backup. Most of the Monsoon vdrives come with a 537 from the factory, & as 85 said it would be a good fit for your needs. The 381 is a dog.

[sledandski]

The 381 is actually a 17.5 pitch and the 537 will be a 16. If you're under 5000 RPM and throwing in that much weight, 537 might be a great fit for you but is still on the steeper side of modern props. You might even gain some top end actually as the pitch difference is almost 10%.

Thanks for the correction, I missed this when typing on my phone.