ALFAGTV6.COM

[kevin]

Just been doing some chassis and Dedion checks from the Alfa sedan to understand their original prop solution . Note I have the Alfa sei Dedion crossmember in my GTV . Matts I have been listening so I dug out the books to see the three d view .
So from measurements the Sei diff sits parallel to the centre line of the car by 75mm to the right side . Also checked the side shafts are of equal length but you can see clearly from drawing the offset of the brake discs . This is viewed from Plan View ie looking down through the roof of the car . The factory drawings shows cross member bolts are exactly 331 mm to centre which concludes the centre of Dedion is spot on centre to the car . You might say this is obvious but remember Alfa does offset certain parts .
This is what I have replicated in my car .
On my GTV the engine sits dead centre with the front yoke centre 30 mm higher than diff . I am fortunate to be able to adjust on my diff as built in space to shim .
Summary my prop is out of alignment in two views but it is parallel . This definitely counts out the use of using one Uj hence the monster vibration from phasing .
The Sei ( 119 ) uses two rubber couplings with a slider on the front so Alfa engineers proved this was the best solution for smoothness back then with the miss alignment as Uj were an option like on the 105 series .
Pity I never had a sei prop when I started this projects but I still probably would not use those old designed couplings anyway . I will keep the BMW one front at this stag as its proven to be bullet proof .

[Mats]

Aha, torque tube. Excellent. Less to worry about.
The offset is of course due to the hypoid gear offset.

Can you measure the angles of the joints? That would give you a lot of info. Difficult to do but very informative.

[kevin]

I still can't work on cars yet and probably until I have had spinal surgery but I have calculate from simple trig that from top view the prop is out by 2.6 degrees as in know its length and its parallel offset . So this is far more than I previously expected as written early . I will get car jacked up and with the App on iPad ( clinometer) I use in construction I can measure the angle in other plane . So its pretty clear One Uj cannot be used in this design .
Now question is does a short one piece prop with a cv joint need a slider joint at the one end ? I would assume NO as the the cv does plunge in and out . Ideas

[MD]

Kevin,

I would assume NO as the the cv does plunge in and out . Ideas

I would not use a slider (Slip) joint based on experience. I have used one at the rear to eliminate the need for dropping the transaxle when removing the shaft and for that reason is it great. However the drawback is less than perfect balance. I put this down to the tolerances between the mating surfaces of the slip joint which are not the equivalent of a solid shaft.

The second reason is that yes a plunge type CV joint does have enough movement for easy removal during servicing so that a slip joint is not really necessary.

Spinal surgery, really ? Far out man !! My heartfelt support buddy.

[kevin]

Thanks that answers my question . I'm going get another prop made with one cv and keep the rubber coupling on front . Then I will get my test driver out to check for me .

[Mats]

The plunge in a CVJ will definetly work, they do on halfshafts you know. They will however not plunge enough to be able to just get them out without pulling the axle rearwards. There is a way but I have to wait o share unil my patent application is filed (yes, really).

[Jim K]

I am patiently waiting for the day one of you guys or someone else comes up with a TESTED, HASSLE-FREE ONE-PIECE driveshaft for sale, preferably without donuts, for less than 1000€. Until then, I'll be watching!
Jim K.

[75evo]

Well it took about 14 years for the headers, so for the CF driveshaft, no hassle fit, ...no bends involved, more space to work with,...... I'd say about 10 years.

[Jim K]

No sweat, I'll probably still be driving at 72.
jim K.

[MD]

Three weeks is a piss poor lead time Jim.

Give us a break.

[kevin]

[quote="MD"]Three weeks is a piss poor lead time Jim.

Give us a break. [/quote]

Ha ! Ha that's pretty funny

Also hopefully this new one piece cf prop can be threaded into position with no effort .

Well their is a rubber coupling replacement used in the DTM days on the 155 which guys are still using make by GKN .
See this link .
http://www.spinning-composites.com

[75evo]

Hey MD,

You may make fun of the Greekster, but he's done a lot. He's been telling the shops/bus/airlines that he is not entitled to senior discounts, and that looks can be deceiving. An honorable man indeed!

[Jim K]

EXCELLENT link Kevin!! Dare I ask about cost?

MD, where do you want your ashes scattered (thrown is a much more appropriate word!)

Jim K.

[75evo]

Jes Thyssen already has a one piece CF shaft, and it costs only 1.2K euro.

[Jim K]

It's ok if its a perfect no-hassle fit.

Jim K.