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so, im sure the first ones cant be killed by the design they will work, HOWEVER, they are NOT going to flex..at all...to which makes me worry about everything else surviving, it looks like its a aluminum plate with 6 holes punched thru it and then a modified leaf spring bushing pressed into the holes..
its going to flex about as much as a solid drive shaft in place..and weve seen those results

those steel "saver" plates i can see working pretty good as they will help keep the bolts from flaring out under high rpm, thus keeping "expansion flex" at bay which imo is what actualy kills them just as much as over flexing
 

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So here's my take, from 45 years street driving and 15+ years track use, of admittedly street-legal low HP and RPM cars, relatively speaking.
The donut itself, I have never seen explode. I have had several cars with them broken clean through, sometimes in three separate pieces, Each piece was still held in and pushed the piece ahead of it. On one car even at freeway speed you couldn't detect a problem (see pics). You had to get under and look. The front driveshaft piece spigots on the ball on the back of the trans. If all is basically well it takes quite an event to allow the driveshaft to uncouple from the output shaft's ball. It can happen, and if somewhat the driveshaft back off the ball, then all bets are off. The donut is mean transmit rotational torque, not keep the whole thing together; that's the ball and bushing's job. But if the nut comes loose and the output flange backs off, the trans mount allows too much up and down, the driveshaft isn't held in place properly, then you're asking the donut to do jobs it was not meant to. I have never had one come apart even at extended 7000 on the track. Race cars get maintained, you hope, way more than street cars so an early problem gets detected. Street car frequently get driven til they break. I have found the output shaft nut completely unthreaded from the shaft itself, and yes, once the yoke flails, it might come through the floor into your leg and lap. But that's no the donut's fault.
I did use a donut saver thingy when I raced, The alum ones seem worth almost nothing in terms of strength to support the bolts at the unsupported end. Cracked very easily. GTA/TI Super steel cage or three-sided triangle, much better.
Andrew
 

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so, im sure the first ones cant be killed by the design they will work, HOWEVER, they are NOT going to flex..at all...to which makes me worry about everything else surviving, it looks like its a aluminum plate with 6 holes punched thru it and then a modified leaf spring bushing pressed into the holes..
its going to flex about as much as a solid drive shaft in place ... and we've seen those results
What will happen is the bushes will move in and out of the aluminum plate if there is any misalignment ... so I agree with you not a good design/solution.

Saying that, with my GTV the front half of the driveshaft is very close to being perfectly in line with the gearbox tail shaft.
Pete
 

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I have had Many giubos explode in 30 years, though admittedly they were almost all original or very old. The new ones above are intriguing.
The first ones up there look like they will be tough and bend a bit, but won't dampen oscillation vibrations very well, in my opinion.
It is Super important that the front and rear halves of a transaxle driveshaft are in good alignment-I made a tool to check them,
and the rear engine mount shims and transaxle crossmember shims are all put back correctly The drive train being even a Little bit out of alignment as one unit is a big cause of vibration around 3K rpm and giubo failure.
 

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i see alot of guys talking about them exploding, and honestly i question if they mean they have tossed a chunk or had a total failure, id bet most of us have tossed chunks but a failure will take out the whole shaft, which as mentioned resides on the ball and comes back to a maintinance issue
 

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Yup total failure on race cars, not from lack of maintenance. Makes a hell of a mess when the tail shaft comes through the floor. That's why many of the cars here run custom set ups.
Have also seen a couple a tail shafts fail due to fatigue from many years of racing.
I doubt those donuts would work. I have seen a similar design from a French car, can remember the model. The have no way of locating the spigot bush's, the shaft would probably flop around like a frog in a sock.
 

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I have tossed many giubo chunks with accompanying sounds as they bounce away, a couple passed me on the road!
But twice in my long years of driving GTV6's hard and far, twice I have had them truly blow up, once the front one blew apart and sent the driveshaft in my direction, breaking the bell housing. Another time, I blew a rear one at 7K rpm and the drive shaft got loose at engine speed and dented the hell outa the floor tunnel around it.
 

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sad but good to hear on both counts, seems to me the only fix still "sound" is the Spruell cage and 600hp MB giubo which is probably seriously overkill for our street cars LOL
 

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Pretty scary because you risk having your feet taken out. Because of the damage I saw on one car I was looking into fitting a scatter blanket of some kind in my alfetta before I lost interest.
I have never seen a cage that fits an alfetta donut, just those gibo savers.
On my friends 105 race car he has a cage and a BMW style donut sold by the usual suspects. Never shows one single sign of wear.
 

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glad im atleast good for a laugh

in all seriousness can the cage and bmw unit be made to fit the fetta/gtv6/milano setup?..i ask because well thats the platform i love, and worse i know the gtv6 has tossed a chunk(vibration), the lloyd since im shoving the engine back will need yet another driveshaft cut on that milano chassis, id just like some piece of mind that its not going to let go with the 3.7 in there, altho the seriously shortened drive shaft will probably help keep everything in check since its almost 3ft shorter than the milano drive shaft set it started out as
 
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