1990 Sunsport Ballast help

Well, I have been lurking on this forum for almost a year. I guess it is time to make a post.

Last July I bought a 1990 Supra Sunsport and had an absolute blast with it all summer. This year it is time to make some improvements. On my list was a tower (found one on craigslist that fit the bill), some sort of delayed convergence device, and a ballast system. The goal is to maintain a flat and level attitude in the water while having a nice even wake to surf.

At this point, I am still deliberating about the delayed convergence device and am leaning toward something like a wakegate. I think I can build a replacement swim platform that will be a little less intrusive to the wake and at the same time integrate the wakegate so no modifications need to happen to the boat. Regardless, that is still being thought about and I may go with a different design after seeing some of the newer creations manufactures are implementing.

So that leaves ballast. The goal here as mentioned is to use even weight, but a lot of it. I am thinking that if people were able to add 2000lbs to their boat unevenly, I should be able to add a little more evenly and not sink it. I will not go willy nilly adding weight though and will add it gradually and incrementally, but I would like to keep as many options open as I can as far as placement and storage. The locations I have seen used are the ski locker (370lb sack?) under the rear bench seats (another 370lb sack?), either side of the engine (750lb sacs) and under the bow somewhere. Either under the seats in the storage compartments (I think 300lbs should fit there but that takes prime storage), or I have seen mention of a location below the cooler. I am thinking the area discussed was the bilge area in front of the engine. Does that go all the way to the front of the boat unobstructed and without fasteners that would rupture a bag? Here is a link that talks about newer boats being able to take advantage of a large front ballast and I just wondered if I could do the same. Are there other locations that I could hide some permanent bags out of sight? I was looking at some photos after the gas tank was removed on Trayson's boat that looked promising, but pretty close to the exhaust. Would that be too hot for a bag? I don't want to add any permenant weight to the boat if at all possible, so the concrete sack Trayson used would be out for me.

Sorry if these are noob questions, but this is my first boat and I am just trying to get as much out of it as I can as it will take me probably 5 years before I can graduate to a newer vdrive. Thanks for all the help you have already provided me and any future help yet to come.

Sounds like you're on the right track. Honestly I can't say if you'd be able to put a bag in the front bow bilge or not. I do know there's some dead space that you might be able to access if you cut a panel in (the space behind the observer storage and under the storage that's immediately in front of that.

If you're thinking under the gas tank, there's not much room there at all. probably 5x18x10.

But yeah, you're on the right track--tube sacks under the rear seat and in the trunk. 750's on either side of the doghouse. You can put another bag in the cooler too. a little one, like 150. the bow storage doesn't hold much either, but it's there.

With the 370 + 750 + 750 I was typically satisfied with my surf wave (for a DD) most of the time--After I installed my surf system that is.

Good luck and keep us updated.

Bottom line, there's only so much room for ballast in a DD

That is what I don't understand. Why is the surf wave going to be better with a vdrive? I would understand if the hull was significantly different, but I was under the impression that they are strikingly similar. I get the two lockers in the rear make it easier to add concealed weight, but if I am willing to add the same weight and sacrifice floor space, and with the new systems starting to level the boats and now even driving the bow down, it would seem a ridiculous amount of weight could be added just the same as in a vdrive and result in the same wake. I do understand that I will need to be more creative as the space was not provided to add the ballast from the get go and that the weight distribution needs to be considered with the weight of the engine further forward in the boat, but that is part of the fun and challenge.

Hopefully I can get the boat out this weekend - I will check out the bilge area out front and see how much space there really is. Is there a reason to not place a sack there from a safety point of view? I would plan on putting in a stop to keep it from sliding back into the engine and remove it a few times each season if not after every run to keep mildew from taking over.

So how did your surf system handle? Just experimenting last summer, I cobbled together a quick surf gate and tried some ballast in barrels to see what the result would be like and I found that the boat was much harder to handle. I used 6 15 gallon drums for about 700lbs and an air mattress in the ski locker bringing the estimated weight to about 1klbs. There were 5 people on board and arranged 4 of the barrels behind the driver and two strapped to the swim platform. Turning right was near impossible and the engine had a much harder time getting things moving (expected with 1600lbs on board). My hope is that evenly weighting the boat and building a power adjustable surf system, the steering would be unaffected. I don't think there is much that can be done as far as the acceleration, but the concern there is with 3000lbs + passengers, would there be damage done to the engine - over heating, oil levels or worse? It is possible that my boat is not well tuned, I did nothing to the engine last year and I do think the carb needs cleaned. How did yours perform? Both the steering and acceleration evenly weighted with the surf system engaged?

Quote:

---

Originally Posted by jnasystems

That is what I don't understand. Why is the surf wave going to be better with a vdrive? I would understand if the hull was significantly different, but I was under the impression that they are strikingly similar. I get the two lockers in the rear make it easier to add concealed weight, but if I am willing to add the same weight and sacrifice floor space, and with the new systems starting to level the boats and now even driving the bow down, it would seem a ridiculous amount of weight could be added just the same as in a vdrive and result in the same wake. I do understand that I will need to be more creative as the space was not provided to add the ballast from the get go and that the weight distribution needs to be considered with the weight of the engine further forward in the boat, but that is part of the fun and challenge.

Hopefully I can get the boat out this weekend - I will check out the bilge area out front and see how much space there really is. Is there a reason to not place a sack there from a safety point of view? I would plan on putting in a stop to keep it from sliding back into the engine and remove it a few times each season if not after every run to keep mildew from taking over.

So how did your surf system handle? Just experimenting last summer, I cobbled together a quick surf gate and tried some ballast in barrels to see what the result would be like and I found that the boat was much harder to handle. I used 6 15 gallon drums for about 700lbs and an air mattress in the ski locker bringing the estimated weight to about 1klbs. There were 5 people on board and arranged 4 of the barrels behind the driver and two strapped to the swim platform. Turning right was near impossible and the engine had a much harder time getting things moving (expected with 1600lbs on board). My hope is that evenly weighting the boat and building a power adjustable surf system, the steering would be unaffected. I don't think there is much that can be done as far as the acceleration, but the concern there is with 3000lbs + passengers, would there be damage done to the engine - over heating, oil levels or worse? It is possible that my boat is not well tuned, I did nothing to the engine last year and I do think the carb needs cleaned. How did yours perform? Both the steering and acceleration evenly weighted with the surf system engaged?

---

A couple reasons. a vdrive has the engine in the rear and those huge lockers. the rear engine means more weight in the rear (not the center) right off the bat. and the lockers = more ability to hold more weight. In my XLV I have 1100 bags in each rear locker and an 1180 bag under the playpen. even with them not filling 100%, I'm running 3000 pounds of weight. the most I ever ran in my sunsport was 350 + 750 + 750 + 150 + 150 concrete. so 2150 tops. That said, it was a decent wave. But not epic. The hull of a more modern wake boat is designed to do just that, make a nice wake. the hull of a direct drive is designed to make a decent slalom ski wake (small).

Also on my XLV I just finished plumbing in 2 more bags that will be about 250 under the front bow surfside seat and 350 under the surfside underseat lockers. If I really wanted to, I could fit another 200 to 250 on the starboard side bow underseat and easily another 350 to 400 under the starboard side seats. So in my XLV I could have well over 4000 pounds of all hidden ballast if I really wanted. There's just simply more room.

I really liked the surf system on my sunsport. the blades only stuck out 3" so at slow speeds turning was affected a little but you could still turn against the blade. with a big old ghetto gate like I've tried on my XLV, there's no flipping way I can turn against the gate at slow speeds. the gate is bigger than my rudder! Plus the NSS style blades on my sunsport were awesome in that they could change sides in under 10 seconds and took 5 seconds to deploy when we were ready to surf. I honestly wish I had a hull that was flat at the stern on my XLV because I'd probably do another NSS style system.

As far as a sack in the front bilge, I know someone on here did it. I can't remember who. Getting access to that space is a whole other story. Keep up the good work, you're on the right track. :-)

you're on the right track. i get a great wave after having installed a malibu-style surf gate last year. do the platform and gate installs together and integrate them, that's what i'm going to do this spring as well. as far as weight goes, i run a 650lb diamond sack under the front seats, fits perfectly. with that and 800's on either side of the motor, you can make a great surf wave. you should upgrade your prop to handle the extra weight though. i went with an Acme 913, 10.5-pitch and it works great.

very interesting you bring up the prop. My boat has a 14' prop on it now and I wondered if it shouldn't still. It tops out at about 42mph at wot, so I was thinking it was a pretty good prop, but am open to different sizes if it will be better performance. I am the second owner of my boat and the previous owner was a slalom skier, so they were definitely not weighing it down. What is the 650lb diamond sack that fits perfectly (is it the sumo sac)? Does it take two of them, or does it end up going over the divider? Or did you remove the divider?

I did end up taking the boat out yesterday and tried looking down the bow in the bilge area. There is an opening on my boat about 6 inches round that I could easily remove for access, but I could not see down there well at all. I will try getting a better light and angle, but there was also something mounted there that looked like it would prevent easy access. At least on my boat, it will be a big project to get access to that space, so for the time being, I will focus on the bow bags mentioned above and making sure to keep the cooler full :cool:.

Quote:

---

Originally Posted by jnasystems

very interesting you bring up the prop. My boat has a 14' prop on it now and I wondered if it shouldn't still. It tops out at about 42mph at wot, so I was thinking it was a pretty good prop, but am open to different sizes if it will be better performance. I am the second owner of my boat and the previous owner was a slalom skier, so they were definitely not weighing it down. What is the 650lb diamond sack that fits perfectly (is it the sumo sac)? Does it take two of them, or does it end up going over the divider? Or did you remove the divider?

I did end up taking the boat out yesterday and tried looking down the bow in the bilge area. There is an opening on my boat about 6 inches round that I could easily remove for access, but I could not see down there well at all. I will try getting a better light and angle, but there was also something mounted there that looked like it would prevent easy access. At least on my boat, it will be a big project to get access to that space, so for the time being, I will focus on the bow bags mentioned above and making sure to keep the cooler full :cool:.

---

that stock prop will give you a higher top speed but will not handle weight well. the first time you run even 1000lbs ballast plus people you will realize that when it takes a minute to get up to speed, if you can get up to speed at all ;) you will lose top end speed but will have a lot more low-end torque to get out of the hole, even with weight. i went from a top speed of around 39 with the stock prop to about 35 with the 10.5 pitch, but it's well worth it. only about $350 as well, it's one of the best purchases you can make for board sports.

the 650 sack i have in front is the sumo sack, yes. stuff it under the front seat and then fill it if you want it hidden, or fill on top of the seat if you want to keep the under-seat storage space.

Quote:

---

Originally Posted by jtryon

you're on the right track. i get a great wave after having installed a malibu-style surf gate last year. do the platform and gate installs together and integrate them, that's what i'm going to do this spring as well. as far as weight goes, i run a 650lb diamond sack under the front seats, fits perfectly. with that and 800's on either side of the motor, you can make a great surf wave. you should upgrade your prop to handle the extra weight though. i went with an Acme 913, 10.5-pitch and it works great.

---

So your running an 800 on each side of the dog house and a 650 under the front seats? is the 650 centered or is it placed on the surfs side of the front seats? i was running 500 in the ski locker, a 750 along the dog house on the surf side, another 750 on the floor between the rear seats and dog house, a 300 on the rear seat and a 300 under the front seats on the surf side. on the rear seat. plus 2 or 3 people. i was getting an ok surf wave, but i know it can be better. i thought more of the weight had to be distributed to the surf side. do you have any pics of your wave?

Quote:

---

Originally Posted by Moor

So your running an 800 on each side of the dog house and a 650 under the front seats? is the 650 centered or is it placed on the surfs side of the front seats? i was running 500 in the ski locker, a 750 along the dog house on the surf side, another 750 on the floor between the rear seats and dog house, a 300 on the rear seat and a 300 under the front seats on the surf side. on the rear seat. plus 2 or 3 people. i was getting an ok surf wave, but i know it can be better. i thought more of the weight had to be distributed to the surf side. do you have any pics of your wave?

---

Yup, front 650 is centered--it is typically under the front seats so it fills up that space completely. I didn't have any pics but I screen-shotted a few from a video the last time out, hopefully they show it a little bit at least.
Attachment 15683Attachment 15684

Quote:

---

Originally Posted by jtryon

Yup, front 650 is centered--it is typically under the front seats so it fills up that space completely. I didn't have any pics but I screen-shotted a few from a video the last time out, hopefully they show it a little bit at least.
Attachment 15683Attachment 15684

---

thats a nice sized pocket on your wave. Definately looks better than mine. I'm going to give your set up a try and see what happens. Your not running any weight in the ski locker or on/under the back seats right?

Quote:

---

Originally Posted by Moor

thats a nice sized pocket on your wave. Definately looks better than mine. I'm going to give your set up a try and see what happens. Your not running any weight in the ski locker or on/under the back seats right?

---

nope, mine doesn't have a ski locker and no additional weight other than people. actually, for full disclosure, with the additional people in the boat that day if i recall everyone correctly, that pic would have been with "people weight" of around 500lbs on the surf side and 400lbs on the starboard side. i have noticed that the wave is best if you weigh the surf side 100-200lbs more than the non-surf side when using the surfgate--so basically weigh it evenly and have someone sit in the rear corner you're surfing. the boat still drives really level and handles much better than when listing.

Quote:

---

Originally Posted by jtryon

nope, mine doesn't have a ski locker and no additional weight other than people. actually, for full disclosure, with the additional people in the boat that day if i recall everyone correctly, that pic would have been with "people weight" of around 500lbs on the surf side and 400lbs on the starboard side. i have noticed that the wave is best if you weigh the surf side 100-200lbs more than the non-surf side when using the surfgate--so basically weigh it evenly and have someone sit in the rear corner you're surfing. the boat still drives really level and handles much better than when listing.

---

I didnt see that you were using a surf gate. That makes a little more sense. I dont have one yet....

oh sorry, yeah i said that in my first post in this thread but the replies are pretty far apart so i can see how you missed it. here's a pic of the first mockup gate that i made last summer, just to make sure it worked. the angle is way more than the angle that ended up working best--i found that 21-22 degrees is ideal for both the wave and handling of the boat.
Attachment 15689

it would be pretty simple to re-create this if you have the same platform, if you just want to see if it works. a couple pieces of wood and offset brackets to sandwich the rail on the platform, which holds it in place. a couple turnbuckles to secure the assembly, hinge, and 15x20" wal-mart cutting board with the hull angle cut out so that the cutting board is flush, and you've got a template. i can send more pics in the next few days if you want.

Please send a few more pics when you have the chance jtryon. I have a teak swim platform, its not the same as yours but i'm sure i can incorporate something similar in design.