Sponson offset

[Gary Lauer]

I am installing new sponson booms from a wreck, and I cant remember which sponson is offset or which is toed in. can anyone set me straight on this?

 

[Steve White]

Subscribed.

 

[derek owen]

I am installing new sponson booms from a wreck, and I cant remember which sponson is offset or which is toed in. can anyone set me straight on this?

from rear of boat left sponson can be further out than the left, poss both with little toe in or right sponson little toe in. think each set up will be slightly diff from boat to boat.. also left sponson slight less A O A sometimes helps

 

[Gary Lauer]

from rear of boat left sponson can be further out than the left, poss both with little toe in or right sponson little toe in. think each set up will be slightly diff from boat to boat.. also left sponson slight less A O A sometimes helps

Derek two lefts?

Steve Subscribed. ?

 

[derek owen]

Derek two lefts?

Steve Subscribed. ?

LOL left further out than the right !! LOL age moment ....

 

[Gary Lauer]

Derek
thank you very much, that is exactly what I need

 

[Steve White]

Derek two lefts?

Steve Subscribed. ?

"Subscribed" to the thread, to see results - interested in topic. Not an original move by me, learned it from others - Monkey See, Monkey Do.

"Back in the day" outriggers had a smaller footprint overall and some, as the early Crapshooters would lift the left front sponson and kite up into a blowover at 80+ MPH. Today's outrigger designs are larger in footprint, which would seem to negate the need to offset the right front sponson outwards to counter the torque.

That's what I was interested in.

 

[Tom Foley]

"Subscribed" to the thread, to see results - interested in topic. Not an original move by me, learned it from others - Monkey See, Monkey Do.

"Back in the day" outriggers had a smaller footprint overall and some, as the early Crapshooters would lift the left front sponson and kite up into a blowover at 80+ MPH. Today's outrigger designs are larger in footprint, which would seem to negate the need to offset the right front sponson outwards to counter the torque.

That's what I was interested in.

Right sponson is toed in and angled up typically to offset turnfin drag .

 

[Steve White]

Right sponson is toed in and angled up typically to offset turnfin drag .

Makes sense - more AoA on the right shoe to compensate for torque loading.

 

[MattSheldon]

In the case of oval participation, couldn't/wouldn't course direction determine positioning as well? Or is torque load compensation the real concern as the boat in theory would then be flat during apex regardless of competition direction?

 

[Gary Lauer]

This is a Coyote Daytona. that I built way back, with a ops .21. I hit a dock with it destroying both booms, no sponson damage and very little tub damage. The plans were vague about sponson setup. From when I ran and know the sport has progressed a lot. Me not so much, so I have to ask a lot of questions and luckily there is so much knowledge on this site and people willing to share it.

 

[Gary Lauer]

would installing= longer booms make a older boat more stable? also is the left longer so it wont lift or to offset torque?

 

[Tom Foley]

would installing= longer booms make a older boat more stable? also is the left longer so it wont lift or to offset torque?

Yes , it does add stability, just don't go too far .

 

[Steve White]

would installing= longer booms make a older boat more stable? also is the left longer so it wont lift or to offset torque?

From the early days, I look at it as the "Aspect Ratio" or inside front sponson width divided into the length of the afterplane which is the rear of the front sponsons riding surface to the prop.

Front end narrow, the boat will rock from side to side and in extreme cases torque roll into a blowover. The other extreme is when the front-end is too wide, the boat will then have a tendency to bunny hop the transom. The aspect ratio years ago was around 2:1. It appears today's boats are a bit lower looking at them. Also, you can run wider if the CG is moved aft, which is also what today's outriggers have compared to older designs.

Optimal is a case by case thing that is dependent upon many many factors. My suggestion would be to try it out, do some testing.

 

[K F Wheeler]

Too complicated for me to understand! Wish I could! Got a .21 Road Runner that I thought about reassembling.

 

[derek owen]

From the early days, I look at it as the "Aspect Ratio" or inside front sponson width divided into the length of the afterplane which is the rear of the front sponsons riding surface to the prop.

Front end narrow, the boat will rock from side to side and in extreme cases torque roll into a blowover. The other extreme is when the front-end is too wide, the boat will then have a tendency to bunny hop the transom. The aspect ratio years ago was around 2:1. It appears today's boats are a bit lower looking at them. Also, you can run wider if the CG is moved aft, which is also what today's outriggers have compared to older designs.

Optimal is a case by case thing that is dependent upon many many factors. My suggestion would be to try it out, do some testing.

my 45 riggers have approx 26 in after plane inside of sponsons vary from 13 -15 ins depending on sponson widths.