GTR CV Joints

[TeflonT]

I have a car with Ultima related lineage in some of its suspension and it uses the same Noble Prosport uprights as the GTR I think.

Question is the (outer) CV joints in the rear hubs, are they the 100mm or 108mm versions?

People say the 100mm versions are a bit fragile and not good for over 350bhp, but I reckon if people are putting 500+bhp through them in an Ultima, they will be fine in my car.

In the picture here http://www.ultimasports.co.uk/Content.aspx?f=gtrco... it does look as though one end (gearbox?) is larger than the other.

Any ideas?

Thx

[macgtech]

Yes you are correct - the inboard are larger and the outboard are smaller, Porsche 934 and 930 respectively

[TeflonT]

So is the general feeling that 100mm end will withstand circa 400bhp/300lb/ft/185mph? I have purchased proper GKN brand joints, which are reputed to be the best, not pattern parts which are designed for Sierra/Scorpio.

The driveshaft angles are pretty much dead straight in normal running, certainly no more than 5 degrees of articulation up/down from bump to droop.

Edited by TeflonT on Monday 23 September 20:52

[ricola]

930 CVs are the 108mm, 934 are bigger still

[TeflonT]

So here is some intersting info:

size 21=934 - 128mm
size 15=930 & Escort/Sierra Cosworth (and others)- 108mm
sixe 13=Std Ford Granada etc 100mm


The early Ultima GTRs had Size 13 outboard ends. These are also what are on the shafts I am using. Takes a massive 4.3kgs off the unsprung weight using the small size 13's over 934!

[845ste]

wow!
Teflon congratulations!
where did you get this information please??
very valuable.
are in trouble and I also would like to understand max torque, corners, etc. max effort

[TeflonT]

http://www.rowland2.com/pdfs/cvdisc.pdf

[845ste]

GRAZIE!!!!

[andygtt]

with 500bhp in my Ultima a few launchs at the strip destroyed the smaller joints

[TeflonT]

Interesting input. What size are the joints on those shafts? 108 or 128mm?

[TeflonT]

Interesting input. What size are the joints on those shafts? 108 or 128mm?

[Ult-Jim]

Interesting, any difference between metal clip ties or wide cable ties holding the cv boot in place among owners? Recently replaced my metal clip tie for a fitted plastic cable tie after the metal tie came loose and made a gungky mess everywhere.

[845ste]

joints
-wheel side? 100mm?108mm? 128mm?but such as wheel hubs? 100mm max .... or is there also changes for hubs?
-transmission side? idem?
he extent to which now uses the factory?
grazie

Edited by 845ste on Tuesday 1st October 21:39

[TeflonT]

Ult-Jim, if you anticipate driveshaft speeds higher than 2000rpm very often (i.e 140mph+) you shoulld use high speed boots on your CV joints. They are like the ones in the image on the bottom right of page 7 here: http://www.gknservice.com/fileadmin/user_upload/Br...

845ste - I'm not sure if the factory has modified the uprights to take at least a 108mm joint. Escort/Sierra Cosworth use a stub axle which can use the same wheel flange and bearings, but it uses a 108mm CV. Factory care to comment?

Edited by TeflonT on Tuesday 1st October 23:12

[TeflonT]

Ult-Jim, if you anticipate driveshaft speeds higher than 2000rpm very often (i.e 140mph+) you shoulld use high speed boots on your CV joints. They are like the ones in the image on the bottom right of page 7 here: http://www.gknservice.com/fileadmin/user_upload/Br...

845ste - I'm not sure if the factory has modified the uprights to take at least a 108mm joint. Escort/Sierra Cosworth use a stub axle which can use the same wheel flange and bearings, but it uses a 108mm CV. Factory care to comment?

Edited by TeflonT on Tuesday 1st October 23:14

[andygtt]

Ultima factory said:

andygtt said:

with 500bhp in my Ultima a few launchs at the strip destroyed the smaller joints

It’s only fair to point out to the readers that your drive shafts/joints were of a different quality and brand to those we supply now, they weren’t Ford Scorpio and they weren’t our current GKN versions either which are fitted with higher quality joints. Yours were supplied by us over 10 years ago and sourced from a 3 year old used car in order to suit your build budget at the time so weren’t even new as you knew at the time of purchase.

I seem to remember quite clearly that I didn't know they were non GKN and hence we had a discussion after this was discovered when they broke, they even came in a GKN box!, it was all very satisfactory resolved back then (11 years ago) so no idea why you bring it up?.... But yes they were well over 10 years ago, not the highest quality and the smaller ones as I stated.

I see that you have dug out an actual picture you have taken of my car to compare old to new... given that this pic was taken when the car was over 2 years old AND it had genuine FACTORY supplied GKN CV joints on the car (supplied after the other ones broke) Im not sure what your trying to show? have you changed the GKN joints since then?... the giveaway are the carbon rocker covers and I fitted these for the next owner.

Thinking back my car was a little unique in that it had small CV both inner and outer rather than just outer like most other Ultimas, this was because of my choice of porsche box.... it was the outer that failed.

Nice trip down memory lane for me though

Edited by andygtt on Wednesday 2nd October 08:53

[F.C.]

TeflonT said:

Ult-Jim, if you anticipate driveshaft speeds higher than 2000rpm very often (i.e 140mph+) you shoulld use high speed boots on your CV joints. They are like the ones in the image on the bottom right of page 7 here: http://www.gknservice.com/fileadmin/user_upload/Br...

Edited by TeflonT on Tuesday 1st October 23:14

Bottom middle of page 6 surely

[TeflonT]

Please don't call me Shirley. But you are of course correct.

[845ste]

i think this is a big problem for those who use it on the track ...... but no one writes here??
only 4 of us??
no one has problems??
do not believe it!
here in Italy I know other 2 last and all problems with joints!
A friend of mine milano matt black has sold out of desperation!
the factory has kindly responded that they have a modified LS engine and gearbox g50/52
However it would be interesting to understand the measures diameters joints wheel side + gearbox side and if they have also changed the hubs: in fact, the most serious problem is wheel side!
because they are smaller and therefore those who break more.
would be nice if every member of the Forums that uses ultima track in saying his opinion.
That's what forums to help, advise each other and exchange views ULTIMA the common dream of all here

[V8Dom]

have you asked Jeff in the USA... he is running over £1000 hp and did over 50000 miles?