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i'm just about to fabricate 6 pieces for my gtv6.now from the pics they appear to be either 1/8 inch thick or 2 milimeter.besides that any one know what type metal is used? i would assume if i had money to burn i would fabricate them out of spring steel with the right amount of give ,but not as much give as the donuts themselves.that would require quite an expense for r&r. but who has money to burn?going from the ridiculous to the practical could any one tell me why they are the shape they are and not simple triangles? for beauty? for the 20(?) grams of weight savings?
 

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could any one tell me why they are the shape they are and not simple triangles?
I would say they need to fit behind the other three bolts that they do not attach to. A simple triangle might cross to close to those other three bolts.

I wish I had seen Larry's post earlier. I re-did my drive shaft a year ago. Larry - do you have pics of the trans-axle ones you make? Are they applicable to Alfetta? I will certainly want to apply these next time. My front donut doesn't seem to last very long.

Thanks,
 

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Yes, they need to be shaped like that to avoid interfering with the other three bolts. A bit of an aside (or fun fact or semi-useful trivia), here's how the donut originally looks on a Montreal. The donut savers are factory mounted, but since the donut has eight holes, it's not of much use for the rest of the 105 crowd.

The savers are 2mm steel. I have no idea of the quality or any other metallurgic properties.
 

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Has anyone made these or know where they can be purchased for the Alfetta?
larry sezs in an earlier post that he made some for the GTV6/Milano but their likely somewhat different.
Same with Wes and Paul's 105/115 solutions.
Low(er) priority but boy adding savers would sure lower the pucker factor when dropping the clutch with all that 'Fetta power. Jocularity aside, these savers just make too much sense not to install. Added security for little to modest effort.
Thanks.
 

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maybe I am showing my ignorance here, but can someone please explain how they work? they perform the same function as the flange on the other side of the donut as far as the bolts are concerned..

Since the shafts are positively located within each other, or at least my Alfetta ones are.. front has a sprung joint which locates in the flywheel and the rear has a hole that the yoke centre fits into.. centre joint I have never removed so can't comment

I can understand the cage style to control centrifugal(petal) forces acting on the rubber at high rpm, but these plates I can't work out. 6 bolt donut, 3 bolted from one flange and 3 bolted from the other.. The flanges on the tailshaft controls the flex of the donut in relation to the 3 fixing bolts for that flange. why bother to put a flange template washer on the far side of the flange..

Is it the centre hole of the plate that keeps the ruptured donut located around the tailshaft end that it is no longer attached to?

Sorry, but i'm feeling a bit daft :) please help me
 

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maybe I am showing my ignorance here, but can someone please explain how they work? they perform the same function as the flange on the other side of the donut as far as the bolts are concerned..
Don't feel bad - I was also puzzled by what those things do. Upon pondering it, here's my thinking:

- The two flanges do nothing to stiffen the giubo in normal operation. The Giubo can flex in torsion just as much with or without the flanges (which is good - the giubo is there to provide some torsional "give" in the driveline).

- In the event of a failure of the giubo, the driveshaft can separate from the transmission. If this happens when the car is moving (and when else would it happen?), the driveshaft can break loose and whip around, tearing out the car's tunnel/floor and possibly injuring the driver (see the second photo below, scanned from an article in the Feb '13 issue of "Alfa Owner" that discusses such an incident).

- The rear flange - the one shown in the first photo below - would help to restrain the driveshaft in the event of a giubo failure. The "snout" of the driveshaft would be captured by the central hole in the flange. That would restrain the driveshaft much more securely than the "olive" at the rear of the transmission output shaft.

- When the giubo disintegrates, the six bolts become cantilevers. As you can see in the second photo below, the centrifugal force of the whipping driveshaft tends to bend the bolts outward, allowing the shaft to come loose. The flanges would help to reinforce the bolts, enabling them to contain the failed giubo + shaft.

 

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I agree with Jay's explanation and that is why I see no need for anything like this on a GTV6 or a Milano as a broken Giubo will not cause the end the drive shaft to whip around. I drove my GTV6 with a totally disintegrated front Giubo and I did not know until I investigated the clunk when I got on and off the gas.
 

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post no. 26.. 2 nd photo, that must have been a wee bit noisy...
 

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The picture above is from a friends car. The donut exploded at well over 100mph, probably 8000 driveshaft rpm. He was pretty severely injured in the incident. I had a similar event happen at Mid-Ohio a couple years ago, but with less severe consequences. An ear broke off of the output flange and took a chunk of the giubo with it. Fortunately, it didn't come completely apart, but it did throw the ear, the bolt and the chunk of giubo through the tunnel, narrowly missing my right leg. The ex-Spruell spider race car I am restoring right now shows evidence of a massive donut failure as well.

The plates that are the subject of this thread work by keeping the 3 flange bolts from spreading at their "open" end. They can help prevent a failure AND help to contain everything if a failure does occur. Based on my experiences, I won't run a stock giubo on a race or street car, even with the plates. The modern BMW style replacements are much stronger. Other than the cost, which isn't outrageous, there simply isn't a downside. It reminds of the question "how much should I spend on a helmet?" The rhetorical response is "how much is your head worth?" The same is true for giubos. "How much are your legs worth?"
 

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The Guibo savers are a decent solution to keep the bolts from spreading. However before I came up with the reinforced german coupling I was amazed at how much the stock Guibo expands under acceleration. Ours were getting wear marks from the cage. I also believe the shields are a prolblem with extra rotating mass. also if you run the "Guibo Savers or the Sheilds in the double shear position with stock style Guibos the plates and/or shield gets pretty beat up by interference with the driveshaft flange. I have to credit Wes for the plates, it was with his permission that I used his for the pattern. It is all about safety.
 

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so there you have it.if you'r in two dimensions you may conclude ,just for the 115 but not for the milano/gtv6.but if you consider as well elliptical forces not on the left to right force plane,but to for aft in any number of ellipses, your sure to come to another conclusion.
 

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Does anyone have the drawing for the Guibo savers, so I can get them cut out of sheetmetal?


I would greatly appreciate the drawing or the .dwg file :)
 

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You can also get them as part of a kit from Spruell that includes a modern Giubo. The modern one yes so much stronger, I’m not really sure the metal plates are that important.
 

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You are protected from an exploding Alfetta Giubo by the tail housing.
 

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They also make the giubos last longer. It would still be a benefit to have them on Alfettas. They are getting harder to find and the new ones don't seem to last as long.

I wonder if the same design, just tweaked for the bolt size of Alfetta donuts would work.
 

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Those pieces like many others will help keep the bolts from spreading out under hard loads. As the forces work on the gubio..... these pieces tend to keep the doughnut supported better. I have seen driveshaft yokes bend without these pieces as well.
 

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Those pieces like many others will help keep the bolts from spreading out under hard loads. As the forces work on the gubio..... these pieces tend to keep the doughnut supported better. I have seen driveshaft yokes bend without these pieces as well.
Sure, in extreme competition use, the bolts and yokes will bend. But what about for normal street use? Do you believe that the Ingram pieces will prevent your rubber giubo from cracking for 85,000 miles instead of 60,000 (or whatever numbers you'd like to insert)?
 
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