I'm new to performance boats and I'm having trouble with learning to drive this boat. My set up is as follows 94 Grand Sport ski with 20" 280 ROS. It has a two hole CLE gearcase with a nosecone added and a torque tab with a 14.5x28 hoss triton prop. 9.5 inch jackplate set at 1/2" below the pad. It has one battery on the port side. I have read the red book and have tried to apply it to learning to drive. When the boat reaches 60 mph it starts to walk but also tries to dart to the left or right. No matter how much I try to compensate with the wheel it just gets worse until I just slow down. I guess my question is does my setup sound like it is good? If so what may I be doing wrong in my driving? Any help and advice is welcomed and appreciated!
Grand Sport help
- Thread starter rfree82
- Start date
msethsmile2 I have not had anyone look at the boat sitting still. The engine is as high as it will go on the current jack plate. People that have been beside me at speed has said the bow of the boat is very low, like plowing low with the trim neutral.
SLOmofo
Well-Known Member
Use the search "grasshopper" with my log on name. Wax on wax off.
Might be the point of the nose cone isn't the same as the prop shaft.
Pictures of the riding attitude can help.
Might be the point of the nose cone isn't the same as the prop shaft.
Pictures of the riding attitude can help.
RiverRat71
Active Member
Welcome to the world of the GS. Dont get discouraged. You are likely over trimming for speed. Tuck her in on take off & take little steps with trim as you progress with speed. If the boat is leaning left it is under trimmed & wont walk. Learn to trim up from there. As you decrease speed tuck it back under a little as you go. I found this the only way to learn my GS. Over trimming for the speed of your ability is where she walks. You are correct in once she walks just starting over. I had never driven a high perf boat before my GS & my friends were all scared of the Allison so I had no help whatsoever but to be honest I have enjoyed every second of it. Like PK & others said balance the weight in the boat best you can. Also make sure your steering has no play. That def will make it much harder. RR
ROBERT CROSS
Well-Known Member
^
X2
Exactly what I had to do with our #1 GS with a 20" 225 Promax.
Trimming up to midway for a hole shot is the only difference with GS #2 with the 15" 200XS ROS.
Patience, seat time, and no drastic moves=success.
Bob
X2
Exactly what I had to do with our #1 GS with a 20" 225 Promax.
Trimming up to midway for a hole shot is the only difference with GS #2 with the 15" 200XS ROS.
Patience, seat time, and no drastic moves=success.
Bob
If you can send us pictures of the lower unit, pad/Lip and try to show us how you are measuring motor Height. that would help us, suggest solutions, if indeed there is a problem and it's not just seat time. Learning to drive and tune my Allison has been one the most fun things I have ever done, take your time and enjoy the process! Lots of us here to help.
I don't have any good pics of the bottom or gearcase. The gearcase is different from what I've seen before. It's a CLE with a cone added to the front to make the bullet longer and also has a torque tab added. The pad has the original lip according to the previous owner and I measure the engine height by leveling the boat and propshaft and measure from the floor to the bottom and to the center of the propshaft
whipper
Well-Known Member
Coned CLE will run like a sports master sorta its a great and tough gearcase and coned even better. I run a modified CLE i did myself and love how it carry's my GS. You have a very potent package with a 280ROS!!! Wish i had one. lol The very best way to get your balancing act together fastest is to have an Allison owner go out with you in your boat and show ya all the little things that make your GS run like its on rails with zero chine walk. If you also do a search Allison chine walking you will find helpful videos hear and there. When you drive an Allison with any motor it is at 60 to 65 and above you have to learn. This can take a month going out every day practising. Thats the speed all grand sports walk up or take a new step and start to ride on the smaller area{the pad}. Its likened like a two wheel bike. Up to 65 you have the width of the hull keeping you stable then as speed increases and you get to the Pad speed 60,s its a two wheel bike and requires you to steer or balance the hull on that very small pad. Hence it was mentioned about counter weight. Normal is about 40 lbs in the opposite gunnel this will help and make balancing easier. Imagine the first time you learned how to ride a bike you had a Back Pack full of rocks strapped to one side of you! You would have fallen over alot! But eventually you will have learned how to counter act that force on the one side and over time ride like your on rails. Same principal applys with learning how to {Balance} your hull while its up in the air riding on that small area, the pad. Without your balancing buy using your steering wheel or handle bars you will start to fall back and forth from one side to the other. Think wobbly steering on a bike. You eventually learned how to require very little in put to stay balanced. Thats how it is driving an Allison. Thats why you need the counter weights also to give your self a fighting chance buy having a perfectly balanced hull in the first place so your not countering the Back pack on your side!! haha Every one who saw your post knew this but its takes time to explain it in a post haha. There is alot more to it but i hope now you have a picture in your head of at least whats going on and that it will take some practice to figure it out. Just keep trying over and over then one day you will get it then you got it, and will never ever forget it. At that point you get it to go fast is simply using your trim. Each bump on the trim makes you have less drag and you will go faster and faster with each bump. Your boat is capable of over 100 mph easy!! So until you learn proficiently and very smoothly on only calm water how to balance try to keep your speeds to a steady 80 to 85 for some time before you bump that trim once or twice more because with your foot to the floor and more trim 90 pluss comes fast with a 280 and slowing down is a whole other chapter. From 80 and under your probably not going to kill your self so keep practising up to 80 then back off REAL SLOW so always give your self room to slow down also. And 100% of the time wear your Life jacket and KILL switch!!!!!!!!! Always!!!!! lol The joy of owning an Allison comes after this learning curve. Then you are part of a very small club of expert drivers because anyone who can learn how to drive an Allison well is considered buy 99.9% of super fast boat people as either crazy or good! haha Take your time dont sweat it. We all for the most part have been in your shoes. Well not all of us with one of the sickest engine combos like yours is but you get the picture. 260 and 280 combo GS is approaching drag boat material and always be safe cant stress that enough! Hears a clip showing some of the hand movements required to balance the hull on the pad at speed. I think my steering was a little loose before i got a new ram so I still have to steer to balance but way less with tight steering.
whipper
Well-Known Member
You dont even think about it but feel it in your but or body and balance accordingly keep her as perfectly flat as possible. I would say my movements are twice what I do now with tighter steering but could have been a slight cross breeze that day also dont recall? haha
SLOmofo
Well-Known Member
If you look at the left side of whipper's video you can see a thin slice of water. Watch this and note the steering input he is imparting to the wheel. As the hull rocks you can see his reaction/input.
When you drive, Don't concentrate on the bow of the boat, concentrate on the horizon in front of the boat. If the hull starts to lean you'll instantly see it and learn to react to it. After a while it will be a subconscious reaction on your part. Your eyes and inner ear keep you in balance.
What I did was go to a calm lake with just a few boats out making wakes. Drove around the lake at at 55mph and played with the trim going over wakes, turns etc. Once I became comfortable, I bumped it up 5mph and started again. 5mph do it again..... You'll find yourself at some point where the boat will lift and then start to chine walk. Bump the steering to counter the rock, if it/as it becomes more pronounced and your behind the curve so to say just back out of the gas before it(chine walk) becomes extreme. Start again.
Balance the hull with objects you always will keep in the boat. I glued a RV level to the uppermost part of the dash directly in front of me.
Go out to practice with only you in the boat. Don't need someone screaming in your ear breaking your concentration, or them moving around unexpectedly. Plus they might never go out with you again. Could be a good thing come to think about it, now that I think about it.
Life vest and kill switch...always clipped and zipped.
Wax on, wax off.....Little Grass Hopper.
When you drive, Don't concentrate on the bow of the boat, concentrate on the horizon in front of the boat. If the hull starts to lean you'll instantly see it and learn to react to it. After a while it will be a subconscious reaction on your part. Your eyes and inner ear keep you in balance.
What I did was go to a calm lake with just a few boats out making wakes. Drove around the lake at at 55mph and played with the trim going over wakes, turns etc. Once I became comfortable, I bumped it up 5mph and started again. 5mph do it again..... You'll find yourself at some point where the boat will lift and then start to chine walk. Bump the steering to counter the rock, if it/as it becomes more pronounced and your behind the curve so to say just back out of the gas before it(chine walk) becomes extreme. Start again.
Balance the hull with objects you always will keep in the boat. I glued a RV level to the uppermost part of the dash directly in front of me.
Go out to practice with only you in the boat. Don't need someone screaming in your ear breaking your concentration, or them moving around unexpectedly. Plus they might never go out with you again. Could be a good thing come to think about it, now that I think about it.
Life vest and kill switch...always clipped and zipped.
Wax on, wax off.....Little Grass Hopper.
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Lotus 50
Well-Known Member
Small corrections. My brother has been driving V bottoms for decades, but his large corrections don’t work with my SS2000