grandsport with 300xs

[bohemian609]

How does the grandsport handle and perform with the 300xs? I'm thinking of going in that direction.

 

[resqu-u]

There are guys successfully running 3.0's the most recent try didn't go so well. Maybe he'll jump on and tell the good and bad of his experience. Here is a link to the story from Scream&Fly.
http://www.screamandfly.com/showthread.php?297980-Grandsport-hooked-hard-right-slowing-down-with-3-0!!&

 

[whipper]

How does the grandsport handle and perform with the 300xs? I'm thinking of going in that direction.

My thoughts is it will work but you need to number one be careful and number 2 be very very diligence in the setup proses. Its wont be a bolt on and go thats for sure.
i would measure were the fulcrum is with a known good top end setup like a 260 or 280. Then i would start with 4 inches of set back and go up from there. i wouldn't think you would be at more than 6 inchs tops. If 4 doesnt give you the right balance point on the hull {fulcrum} i would start by moving the battery to the front then if you still need more the gas tank with 10gals of gas in it might need to be go ahead an inch or two. If you do these things hats a good start. If your not willing to i wouldnt bother.

After the setup then comes driving the high torque motor off of speed more than the run up. Prop selection will be key. if you are willing to go the extra mile I would install a taylor 15 inch mid with the 3.0 top and 2.5 bottom. If you go with the SM 2.5 1.62 case you will be way better of even though I think setup will solve alot of the issues with baking off with a bigger wheel. DBR can also stage 1 the motor so you have increased revs so you wont need as big of a wheel for a great number. A smaller wheel will lessen the parachute effect of backing down than the bigger wheel needed with only 6000 rpm.

thats my take on it and what i would do or I wouldnt bother.I do like the idea though allot. I would take everything slow and get very used to the combo before I ever thought about trying for speeds much over 90. you may also need wedges.

 

[bohemian609]

Thanks for the input

 

[Allyfishing]

How does the grandsport handle and perform with the 300xs? I'm thinking of going in that direction.

contact harrells here and ask his advice. He has a 250XS with 1.62 gears/sporty and has his running great. The setback with be different with the 3 liter over the 2.5 liter as well as the engine height.

 

[catfish123]

Yep Craig, that would be a great place to get set-up information that has been proven to work and work well.

 

[whipper]

A 250 will be a little different than running a 300xs. But for sure Mr Harrells set up would be a great place to start. His setup is close to Badbaits XB03. Bill was one of the first to try this. We have been talking about putting a 300xs on a GrandSport for a long time now. Ive talked to Darris and others in person and over the phone for hours about this. The biggest issue is respecting what your setup is. Most people wont respect this is the liability behind it. Even the way most have there setup with the 250xs theres more that can be done to perfect it. Just running a lesser setback is not the best approach even though is will work. There more forces at play at different attitudes. Personally i would rather a 300xs setup that i can chop the throttle at 90+ with no real ill effects as my 225 does on the back now. That can be achieved I have no doubt. It just takes time and testing like anything. But the respect factor is whats going to get someone very injured or worse. The only set-ups I've heard of that bit back hard were over 6 inches of setback with no other mods. Thats just asking for trouble. Take your weight into account at the helm over someone else's setup. It all is going to play a factor in the responsiveness of how the stern and bow react with the power curve of the 300xs over a 250xs.

 

[propmanjay]

I have seen Badbait "Bill Smith" run his xb03 with a 250 many times. He has very good stability with his set up. He also runs 102 with it any day of the week while sipping fuel!!!

 

[ziemer]

There are guys successfully running 3.0's the most recent try didn't go so well. Maybe he'll jump on and tell the good and bad of his experience. Here is a link to the story from Scream&Fly.
http://www.screamandfly.com/showthread.php?297980-Grandsport-hooked-hard-right-slowing-down-with-3-0!!&

Yep, that'll happen when you take no one's advice and think you know everything. It was for sale within a week of this happening too. :rolling eyes

Will it work? Sure, it will just take patience and proper setup. It won't be as forgiving as a smaller 2.5. :at the bar

 

[LakeAnna]

Yep, that'll happen when you take no one's advice and think you know everything. It was for sale within a week of this happening too. :rolling eyes

Will it work? Sure, it will just take patience and proper setup. It won't be as forgiving as a smaller 2.5. :at the bar

Agreed! !

 

[mikesufka]

300XS is the best motor I've ever owned. The Allison Grandsport was probably the most fun to drive. Now to combine them.....

MDS

 

[whipper]

Yep, that'll happen when you take no one's advice and think you know everything. It was for sale within a week of this happening too. :rolling eyes

Will it work? Sure, it will just take patience and proper setup. It won't be as forgiving as a smaller 2.5. :at the bar

x2

 

[whipper]

300XS is the best motor I've ever owned. The Allison Grandsport was probably the most fun to drive. Now to combine them.....

MDS

Thats what I have always thought also. If i could have afforded it i would have done this already hands down. But not for a top end number. Though that may come much later. Just for the challenge of the setup and great skiing torque.. One thing is for sure there are now some options that were not available as readily as there is now for decreasing the the top heaviness of the 505lb behemoth. Light fly wheel,light carbon cowl,more revs, 2.5 gear-set shorter mid. Just more doable but not cheep to convert. A set up like Bills and Mikes seems pretty good. There is even room for improvement thats the cool part. Theres a thread some were about this but If I remember right Bills running 3 1/2 offset? Not sure about any wedges. i know the 300pm ran around the 4 inch off set with 3 deg wedges. The fellow who hooked was running 7 that's a little to far back unless he weighs 260+ lbs. Even then a little to far back with out changing ballast compensate. A 50lb battery is 100lbs off set when placed in the bow for instance. If the math is right it will work. But I wouldn't suggest for a second it would be a wise idea to do this unless you are totally dedicated to taking all the procations of setup and are clear that it could be very dangerous to attempt!

 

[xb03fs]

I cant imagine wanting to add weight the bow. Sure it would help holeshot, sit better at rest and maybe fly a little better, but adding weight to the bow would surly make hooking more likely....

 

[whipper]

You sure dont want much but these hulls love having weight in them with 3.0lt motors. they are more stable with 4 in the boat than solo with power. The way with a non ratcheting case you have to come off is slow and steady keeping the bow from dropping fast. The fulcrum point is whats most important. With a 2.5 sub 400 lb motor what they are designed around your fulcrum is were its suppose to be with an average sized pilot just behind the front seats.. With a 505 lb motor its way to far back and the fat guy makes the skinny guy in the bow unbalanced unless ya let him hold the battery even with less setback on the teeter totter. Its going to be different for every one. Hulls off set differences driver sizes. Its just one way some have {ballanced} there hulls to be were they are designed to run as an example. I drew up a slider weight and fabricated it at work last year. its going to run down the keel line under the floor for 4ft. It has 4 pin points and a small SS anvil that will be slid into place to archive two things. Keep the centre of mass as low as possable and make finding the fulcrum point easier. Im going to use a crane to determain the EXACT spot were mine is if i ever can afford a 300xs. A few years ago I was at buddys shop were he was outfitting a new 300xs on a STV euro. The fulcrum was way out and the feel wasn't right. This guy has over 8 world speed records and knows what there suppose to feel like. haha He moved the battery forward and the gas tank 2 inches with 3 inches less setback. Those little changes put the balance were it should be to react to trim and run better all around. Theres also the bigger wheel and massive torque to factor in with setup. So having a little weight in the bow for instance isnt a bad thing as long as it isnt enough to throw the ballance of the hull to far forward when backing off. I took most of the lip off mine for instance. That reduces the bow drop greatly but has its other challenges with setup even with just a little old 225. It Took allot of pad work adding and sanding testing and trying 3 or 4 setbacks reshaping the gearcase and counter weight to get her to run the way I liked. Theres more ways to skin a cat! Personally I like playing around trying different things. Thats all i do all the time. I have probably given this more obsessive thought than most and called everyone in north america who i know would have some feed back on this and the math on paper 100 different ways. When ever someone says no I always try and find a way. {its an illness} i don't want anyone to get hurt just the same as everyone else on hear. i haven't even done it yet but I have a pretty good idea were to start. If there's an idea that someone can take to help them in doing this that hasn't been tried then great. I feel its prevalent to elaborate instead of just say it will or wont work. why will it or wont it. There are a few running with success now so it can be done. i would say just not for the average guy because of the risks with going outside the box.

 

[whipper]

Hears a little power head that might do well.:shock: The little blue tabs is were the Nos goes. Note the duel spark heads.. This is something like Gary would run. haha