Brad Christy
Well-Known Member
- Joined
- Jun 24, 2002
- Messages
- 1,390
Guys,
Since everybody is convinced that a 21 hydro can't run 80+ MPH in heat race trim, I curious as to why not. Are the engines just not strong enough? Is it the props? Is it that the hulls, being so light, won't handle the speed? Or is it that the guys who HAVE done it (and it has been done, repeatedly) haven't told the rest of us how they did it?
If it is the engines, it is only a matter of time until it is commonplace. In the mid to late 70's the open hydro class SAW record was somewhere in the low 70's (this was before my time, so I'm not sure of the dates or exact speeds). Now it is over 120 MPH and the 45 hydros are in the racing in the high 80's.
Has the right prop not been designed yet? I think it has. If you do the math for an Octura 1650 or ABC 1718, the theoretical speed potential is well into the eighties. With the 1650 at 30K RPM, you're looking at nearly 90 MPH. Now, I know you have to account for pitch slip, but the faster a hydro is traveling, the more efficient a prop gets due to the virtual lact of hydrodynamic drag.
Is a 21 outrigger too light to stay on the water at these speeds? I can't see how this is logical, since the SAW record is nearly 100 MPH. I know that this boat will not heat race worth a darn in the configuration it set this record with. Still, it shows that the proper balance of lift and downforce CAN be achieved to let the boat break free of the water but not let loose and go hurling through the air.
I feel that this is not only possible, but not that difficult. Just because something has not yet been done (which is not the case in this instance), does not mean that it cannot be done. JFK once said that we would not only put a man on the moon, but it would be done "In our lifetime", and most laughed at even the possibility.
Can of worms? You bet. Let'm loose.........
Thanks. Brad.
Titan Racing Components
Since everybody is convinced that a 21 hydro can't run 80+ MPH in heat race trim, I curious as to why not. Are the engines just not strong enough? Is it the props? Is it that the hulls, being so light, won't handle the speed? Or is it that the guys who HAVE done it (and it has been done, repeatedly) haven't told the rest of us how they did it?
If it is the engines, it is only a matter of time until it is commonplace. In the mid to late 70's the open hydro class SAW record was somewhere in the low 70's (this was before my time, so I'm not sure of the dates or exact speeds). Now it is over 120 MPH and the 45 hydros are in the racing in the high 80's.
Has the right prop not been designed yet? I think it has. If you do the math for an Octura 1650 or ABC 1718, the theoretical speed potential is well into the eighties. With the 1650 at 30K RPM, you're looking at nearly 90 MPH. Now, I know you have to account for pitch slip, but the faster a hydro is traveling, the more efficient a prop gets due to the virtual lact of hydrodynamic drag.
Is a 21 outrigger too light to stay on the water at these speeds? I can't see how this is logical, since the SAW record is nearly 100 MPH. I know that this boat will not heat race worth a darn in the configuration it set this record with. Still, it shows that the proper balance of lift and downforce CAN be achieved to let the boat break free of the water but not let loose and go hurling through the air.
I feel that this is not only possible, but not that difficult. Just because something has not yet been done (which is not the case in this instance), does not mean that it cannot be done. JFK once said that we would not only put a man on the moon, but it would be done "In our lifetime", and most laughed at even the possibility.
Can of worms? You bet. Let'm loose.........
Thanks. Brad.
Titan Racing Components