Driveshafts

Author
Discussion

adequatespeed

Original Poster:

87 posts

275 months

Wednesday 28th August 2002
quotequote all
Is anyone else running Granada drive shafts on their Ultima.

I have managed to explode a CV joint and last week whilst giving it a bit of jip away from the lights ripped a drive shaft in two!

Very embarrassing!

However, it did make a very satisfying crack when it let go.

I am a bit concerned weather the Ultima spec shafts (which are a similar size) are truly up to the job considering the ease by which I have destroyed the ford units.

bluesatin

3,114 posts

272 months

Wednesday 28th August 2002
quotequote all
I have the factory spec shafts and they have been fine for me. The engine gives 525bhp and i really go for it (especially with traction control). The factory claim they are rated to 1000bhp (I think).. Are you going to the club meet on Sat?

>> Edited by bluesatin on Wednesday 28th August 17:36

GreenV8S

30,193 posts

284 months

Wednesday 28th August 2002
quotequote all
quote:
Is anyone else running Granada drive shafts on their Ultima.

I have managed to explode a CV joint and last week whilst giving it a bit of jip away from the lights ripped a drive shaft in two!

Very embarrassing!

However, it did make a very satisfying crack when it let go.

I am a bit concerned weather the Ultima spec shafts (which are a similar size) are truly up to the job considering the ease by which I have destroyed the ford units.



I've got nothing like that sort of power, but got through three or four half shafts on the V8S before upgrading to some custom ones from Tower View. I also changed up to the larger size CV joints. (You may be using the larger size already?) In my case the half shafts went close to the circlip groove just outboard of the inner CV (if you see what I mean). This makes a fine stress raiser, and Tower View had some slightly thicker shafts made up without this groove. A lesson I learned is to replace the half shafts in pairs - they seem to fail due to fatigue, and when one goes the other will soon follow.

Cheers,
Peter Humphries (and a green V8S)

bigmack

553 posts

260 months

Wednesday 28th August 2002
quotequote all
I've been told that the Ford units are not designed to accept a lot of torque from a dead standstill. The other half-shafts that Ultima sell are made by GKN. They are much stronger. GKN has a website. Still, you have to remember that we're talking about half-shafts...not a solid axle. Here in the U.S. half-shafts drive the drag race sanctions crazy. They just can't stand them in conjunction with high output motors. There are even some bans on them. I'd get the GKN units. They're very good.
Cheers!
-Mack

shpub

8,507 posts

272 months

Thursday 29th August 2002
quotequote all
quote:

I have the factory spec shafts and they have been fine for me. The engine gives 525bhp and i really go for it (especially with traction control). The factory claim they are rated to 1000bhp (I think).. Are you going to the club meet on Sat?

>> Edited by bluesatin on Wednesday 28th August 17:36



One of the advantages of traction control is that it is incredibly kind to the transmission and helps prolong the life of the bits.

Steve

bluesatin

3,114 posts

272 months

Thursday 29th August 2002
quotequote all
Steve

I thought this with TC but when it hits the hard cut limiter all hell brakes loose with flames out of the exhaust. I think it can be quite kind on 0% slip but if you run 10% slip it allows you to floor the accelerator then cut back on the power. From experience the security it gives allows you to be more brutal with the car than you would without TC- my rears show this. I used the car for about 3,000 miles without TC and no probs.

GreenV8S

30,193 posts

284 months

Thursday 29th August 2002
quotequote all
quote:

Steve

I thought this with TC but when it hits the hard cut limiter all hell brakes loose with flames out of the exhaust. I think it can be quite kind on 0% slip but if you run 10% slip it allows you to floor the accelerator then cut back on the power. From experience the security it gives allows you to be more brutal with the car than you would without TC- my rears show this. I used the car for about 3,000 miles without TC and no probs.



Main advantage from that pov is it stops you spinning the wheels up when they're unweighted and then mashing the transmission when the weight comes down again. It doesn't stop you stepping off the clutch which is what takes out the half shafts (abrupt transmission wind-up).

shpub

8,507 posts

272 months

Thursday 29th August 2002
quotequote all
Every little helps as they say. While not an Ultima I was chucking 360 ish bhp through a TVR Wedge whose half shafts are reknowned for breaking at a second glance and they have survived 3 years sprinting, hill climbing and track/test days.

This year with an upgrade to 400 ish bhp, they died within a couple of months and the rear transmission had to be uprated. I did change the slip value to nearly 10% so maybe I was asking for it. Now running UJs courtesy of Massey Ferguson...

GreenV8S

30,193 posts

284 months

Thursday 29th August 2002
quotequote all
quote:

Every little helps as they say. While not an Ultima I was chucking 360 ish bhp through a TVR Wedge whose half shafts are reknowned for breaking at a second glance and they have survived 3 years sprinting, hill climbing and track/test days.



No fair comparision Steve. Those tubular Jag half shafts used on the wedges are massively stiff torsionally and they are easily capable of dealing with the torque. Not like normal (much thinner, solid) half shafts which are vulnerable to wind-up and are very marginal under high torque. Don't know how the UJs compare to our CVs (stronger I would have guessed) but you should have no trouble at all with the actual half shaft.

shpub

8,507 posts

272 months

Friday 30th August 2002
quotequote all
Well it all depends. I was talking to a guy who works at ProDrive who was saying that CV joints are better than UJs at delivering torque through extreme angles. So it seems that the ideal solution would be the huge tubular halfshafts hooked up to CV joints...

I must admit if the tractor stuff doesn't hack it I'll move over to CV joints and see if that improves things.


GTRCLIVE

4,186 posts

283 months

Monday 2nd September 2002
quotequote all

While on my third run down Santa Pod last month, One porsche ( early 915 )shaft bent like a bannana, the other snapped at the CV joint. So have bit the bullit and fitted the factory shaft's. All good so far.
What was annoying it was a perfect start of the line then they snapped going into second. Only pulled a 12.1 second first time out ( loads of wheel spin ) second redlighted third Bang!! Trying my hardiest to break Ted's no luck so far !!

GreenV8S

30,193 posts

284 months

Monday 2nd September 2002
quotequote all
quote:

So it seems that the ideal solution would be the huge tubular halfshafts hooked up to CV joints...



Would be interesting to see what that did to your rear wheel camber control?