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Discussion Starter #1
Working on my Alfa Dio Tipo "Special" street/track day build.
Now mocking up the drive-train and chassis.
Not thrilled with the bulky and too prone to failure Guibo.
It will be right next to my knee, so despite incorporating driveshaft safety hoops I'm looking for a better design.

Tried to search the site but did not find any threads on replacing the Guibo with something stronger.
Seems there should be a kit available to convert to a CV joint.
I can make an adapter but if it's already available that would be faster and simpler.

If not available I wonder if there might be interest in my producing them?
 

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Richard Jemison Alfar7 has one on his race car.
 

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Sprue and others have a BMW "gubio" that is much more reliable than the original. Needs some spacers to fit properly - which they include.

Others may also supply the same.

Robert
 

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Sprue and others have a BMW "gubio" that is much more reliable than the original. Needs some spacers to fit properly - which they include[/QUOTE

It is a good product but the instructions included with mine were incorrect. I posted the correct positioning of the spacers.
 

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A CV joint is a poor substitute for a Guibo

Implicit in these "...replace guibo with CV joint.." threads is the assumption that a Guibo and a CV joint serve the same purpose. They don't, it's not even close.

The function of a guibo is to dampen the torsional vibrations generated from the engine.

The purpose of a CV joint, is to give an axle enough freedom of motion to do it's job. To let the axle expand and contract in length as the wheel goes up and down in a IRS or IFS arrangement. CV joints also let the wheel pivot, a necessity for FWD.

Most cars don't have guibos because they have automatic transmissions. The fluid drive in the torque convertor is a poor transmitter of torsional vibrations, and acts as a break in the transmittal chain of vibrations.


There have been many thread about this subject, you should search them out.

Bye
 

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Discussion Starter #6
This will be as close as our modern society will tolerate to being a race-car on the street.
Short one-piece driveshaft and the front connection right at my hip as the engine is set back as far as possible.
A guibo is bulky in addition to less than ideal strength.
Flimsy fiberglass body attached via Dzus fasteners to a tube frame with riveted on aluminum floor and no sound deadening.
I have to wonder why ALFA really went with the guibo, seems perhaps more for driver comfort than absolute necessity.
I've owned and thrashed many other cars that got along just fine with a conventional u-joint at each end of the drive-shaft.
Torsional vibration may not bother me but a failed Guibo certainly would even with the driveshaft well caged.
Despite very limited rear axle movement I still have to allow for some deflection, the CV seems the best answer to replace a guibo.

I did do searches, perhaps the sheer volume of post here makes them ineffective, or maybe Groucho failed to share the secret word?
 

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Torsional damping is necessary to ensure longevity of all transmission components, period. If you feel you must discard the standard giubos, or the Spruell BMW type, then consider the tube-within-a-tube arrangement made by Bailey Morris in the UK. In effect, this turns one of the propshaft tubes into a long metallastic bush/silentbloc, which can handle all the torque whilst damping out the engine pulses. These guys definitely know what they are talking about and would be able to make a one-off propshaft for your application, for a reasonable price.
 

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if the car's going to explode without a giubo, you might want to tell that to the many other cars that run fine without giubos in the driveline. My TR7 had CV joints at both ends, for example, and it sure wasn't an automatic transmission.

Richard, I assume you've seen the carbon fiber driveshaft that Centerline is selling? It has a CV joint at the front. There's been some discussion here but no direct feedback yet.
 

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British Leyland has bugger all in common with Alfa Romeo high engineering practises. Think I'll bow out of this thread now ...
 

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For my money, I'd get a set of Wes Ingram's "Guibo Savers" for $60 and spend my time, cash, and engineering development skill elsewhere.

"Guibo Savers

We have been using these Guibo savers on all our performance and Race Alfas for over 15 years and have never had a failure.

In 2012, we made several 1/4 mile acceleration runs at our 1/2 mile test track near our shop with Red Ryder. This was the first time I tested any 105 chassis and running gear for full hard/launch drag race results. On 6 different runs, we floored the throttle to 8000 rpm, dropped the clutch and with the Limited slip layed down about 20 feet of black rubber with the 9 in. wide Toyo's. I was prepared and expected that something would break, but there were no failures. To my surprise the car launched perfectly straight with just enough wheel spin to not bog the engine. This was with our best 1750 engine to date that made 200.4 HP @ 7100 rpm and 162.1 ft lbs torque at 5300 rpm. Our 1/4 times were 12.85 seconds at 105 mph.

The savers attach to the unsupported ends of the bolts, not on the yokes. They contain the ends of the nuts and bolts on opposite ends and prevent them from spreading at high rpm. Cost is: $ 60.00 per pair of two.
"
IMG_0523.JPG


http://www.wesingram.com/vprep.htm


Tangentially, I also note that Wes Ingram retains the guibo in the drivetrain of his race cars.

FWIW
 

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But Mad North-Northwest
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British Leyland has bugger all in common with Alfa Romeo high engineering practises. Think I'll bow out of this thread now ...
Yeesh, that was just one example of many.

And don't get all ****y about Alfa. At least BL made synchros that worked :D
 

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There are many cars with guibos in the drive shaft, there are many cars without them using the good old cross type u-joint. And some newer car use CV joints in the drive shaft, the Honda S2000 being one.
I'm sure the designers and bean counters have their reasons for what we find in the drive train, and whatever is used seems to work pretty well. Claiming this or that must be used or can't be used just isn't supported by the evidence.
 

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My club race car had a driveshaft about 1 or so feet long, and had UJ's each end. Never had an issue, but also did not do 100,000 miles with this car either. Alfa Sud engine, Ford 4 speed gearbox and Ford rear axle.

Pete
 

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Hi, for what its worth I ran a racing Alfetta 2 litre GTV with a CV at the front flywheel and conventional universals at the centre and rear positions for some time.
As there is inevitably a small amount of slack in these joints the rattling at idle would not be acceptable in a road car, but OK in a race car. Having a very lightweight engine flywheel doesn't help. Of course the whole assembly was balanced.
I eventually went back to Giubos, at least in the centre and rear positions.
The problem was shearing of the clutch input shaft, luckily always at low speeds. Despite the spines being tight and using thread lock the constant hammering at idle fatigued the shaft. I broke three shafts before finally giving up.
George.
 
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