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Backfire
11-28-2001, 10:45 AM
I saw a discussion somewhere recently between le13 and another ss or ps guy in which they were commenting on the use of 7/8" propshafts in the superstocks and perhaps other classes. I'm curious if Lance Falkner's failed propshaft on his new GN boat was 7/8" and if these will now be outlawed?

superdave013
11-28-2001, 11:18 AM
I would not think that was a 7/8" shaft of his GN boat. From what I read in that same thread between LeEss13 and 126 driver was the 7/8" shaft can handle the h.p. of a S.S. but not more. All of the GN boats that I have looked at run 1 1/8" shafts.

e-ticket
11-28-2001, 11:30 AM
I/ve been told by my engine builder (Jim Lange of Hi-Tech Marine) to upgrade mine from 1" to 1-1/8" for my blown motor application to handle the power and torque in my 21' Howard. (All it is, is money and safety!)

126driver
11-28-2001, 01:15 PM
It was an 1 1/8" shaft. The main theory is that an ear was thrown off of the prop and the severe shaking cracked the coupler. The safety collar couldn't handle the stress and the prop slammed back into the rudder. I wasn't at the river, didn't see the crash, and have not seen the prop, (nor do I care to) but have firsthand info from a reliable individual. Probably no one will ever know for sure, and from a personal standpoint, it doesn't even matter to me. It's just a huge tragedy and a tremendous loss.
Scott
PS, I don't mean to sound like I'm coming down on anybody. People are curious as to what the cause is in the event of a mechanical failure, and for good reason I know. We have used 7/8" shafts in superstocks for several years now. They break on rare occasion. I had one break on me last year. Keep in mind we're running in the neighborhood of 600 - 650 HP, and the shaft gets replaced once a year, regardless of the appearance. No doubt, replacing that 1" shaft is a good move on a blown boat. And double-check all of those safety collars. I know we will, but sometimes, shit happens anyways.
[This message has been edited by 126driver (edited November 28, 2001).]

Stab-n-Steer
11-28-2001, 02:33 PM
126 Driver,
First I would like to extend my condolences to you and the whole SS community. I know you are a close knit group and Lance was a close friend to all.
I don't mean to be critical but the 7/8" shaft you guys run seems crazy to me (I understand this was not what Lance ran in the GN.) A 1" shaft even though it's only 14% larger in diameter it's 33% stronger. I would assume you guys run 4140 shafts, not the stainless stuff us hobbiests run. It would seem like the shaft dia. would be a good thing to have a rule on so it's the same for everyone...
What about offset rudders like the drag boats and the circle hydros run? I wonder if that would that have helped prevent the prop hitting the rudder in Lance's case?
I am not a boat racer so these are probably stupid questions. But look at what NASCAR is going through right now, they had to have a few deaths before safety rules are put in place. Boat racing in general is dangerous but anything to minumize the danger seems to make sense to me. I'd rather see you guys go a few mph slower and have you around to have a beer with after the race...
Again, I am very sorry about the loss of your friend.
Randy

Unchained
11-29-2001, 09:54 AM
It seems like any mechanical failure causes an immediate crash with the V-Drives. This recent crash follows a long list of,
the coupling broke and he crashed,
The propshaft broke and he crashed,
The engine siezed and he crashed,
The prop broke and he crashed,
The strut broke and he crashed,
The rudder broke and he crashed.
The cav plate mount broke and he crashed.
Just my observation, I still plan to buy the 21' Daytona V-Drive though.
I'm a little tired now, I need to go in the other room and crash.