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IRS 960 estate with G90?

Turbeam said:
Did you ever pull that one apart... I'm curious as to what actually failed? Was there a lot of torque/ tyre being used, or perhaps very hard launching when it failed?

One of the attractions to me of using the Volvo live axle in the first place was that they have such a good reputation for strength.

So, on the axle in question, it could either be that despite being a 3-litre 960 Estate that the UK IRS versions DIDN'T get a G80 from the factory as standard (which would be slightly surprising), or it could be that the stock G80 HAS failed or stopped working in some way (which would also be a little surprising).

I doubt that there will be any evidence of factory spec tags remaining on this axle!

Rear cover off time I reckon.
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I had pulled off the side of the road and spun the tires to get back on the road, the only thing I can think happened was there was a really large difference in traction as one wheel got on the roadway and one was still in the grass. I've spun the tires in 1st 2nd and 3rd on surfaces with the same traction and have had no problems. The governor weight was split in half and the shaft it's mounted on looks like it went through the ring gear. there was some clunking and binding when it broke, but after the parts settled on the bottom it went back to operating as an open diff.
 
FlyingTog said:
For the record, my IRS 960 has over 237k miles on it on the stock G80 equipped rear axle and it hasn't broken yet or stopped working. And I beat the ever loving shyt out of my car. Clutch kicks, burnouts, hard launches, etc. It takes it like a champ. I've put almost 100k miles on the car (97k+) personally and it's still going strong. Only thing I did was when I had the rear suspension apart when I did the coilovers, I welded the weight inside the G80 to keep it from unlocking above 30mph. Other than the associated flush and fluid change when I did that, the rear axle is stock with close to 240k miles.
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I'm not yet putting anything like the torque through my G80 that the guys with +T motors would be, or even running up very much annual mileage, but over the last 6 years or so when it has been getting used it has had to put up with a fair bit of harsh punishment... all without ever giving any trouble.

I still believe that with the right level of mods these units can offer a good compromise of benefits without need of regular maintenance or replacement for wear reasons as would be the case with alternative types.
 
VB242 said:
I had pulled off the side of the road and spun the tires to get back on the road, the only thing I can think happened was there was a really large difference in traction as one wheel got on the roadway and one was still in the grass. I've spun the tires in 1st 2nd and 3rd on surfaces with the same traction and have had no problems. The governor weight was split in half and the shaft it's mounted on looks like it went through the ring gear. there was some clunking and binding when it broke, but after the parts settled on the bottom it went back to operating as an open diff.
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It has probably been a big torque difference acting across the diff before the unit has had a chance to fully 'ramp-up' and lock.

I don't fully understand how that could have happened .... presumably the diff was already locked when both wheels were spinning on the grass and there was a big shock loading as one tyre got grip on the tarmac, but that is pretty much what it was designed to do?

The actual rotating lock-up mass and its mounting are not particularly stout looking, but they normally only have to bring the friction plate end pack and ramps into hard contact to affect locking, after which they are mostly unloaded?
 
monty400k said:
crogthomas said:
What are you actually trying to do? Your Sunbeam has a live axle, so why the interest in the 960 QUOTE]

It's not for the Sunbeam, it's for my 960, i am also planning to fit a supercharger later this year which Jim has been advising me on, one thing ive been concerned about is the lack of traction, we have been trying to work out if my car has an open diff or not, i had a look this morning and its a 1055 as i suspected so I will need to look for a 1065
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Did you find a label on it or did you have to remove the cover Jonathan?

I'm a little suprrised that a later model UK 960 Estate doesn't come as stock with some kind of differential anti-spin device fitted, G80 or otherwise.

I guess that one of those must now be very high on your wish list...I think it would make a huge difference to your car even before adding a supercharger.
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Am I right in thinking that a G80 from a 1041 axle is not compatible with the IRS diff casing for some reason?
 
VB242 said:
I don't really know what happened but here's the link to my busted G80 thread with pics of the damage. I cut my governor weight as opposed to welding, I will weld the next one if this one (cut governor weight as well ) breaks.

http://forums.turbobricks.com/showthread.php?t=283229
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Thanks for the link. That is really strange, it hasn't failed in the way I was expecting at all!

The little rotating barrel part is responsible for lock up, the larger mass only moves outwards at higher rotational speeds to disengage with the much smaller weights on the 'barrel'.

With the disengagement mass reduced by cutting it down, the same spring force on it should be able to control it more easily and raise the disengagement speed.

I'm struggling to imagine how the big mass could have got damaged and its shaft so badly bent as a result of it disengaging?... and if it happened during engagement (at which point a mass change should have made no real difference), surely the lighter and much less robust 'barrel' and its axle/ pin would have suffered the greater damage as a result, and yet it looks to be OK in the photo?

It almost looks as if it has caught on some part of the diff casing in some way as it has been rotating to have been so comprehensively destroyed, but that shouldn't even be possible!

Very strange indeed.

At least I have only reduced the weight of my disengagement mass a little rather than cutting it off completely as I wanted to retain the disengagement function albiet up to a slightly higher speed. Hopefully I won't have any similar problems.
 
Turbeam said:
monty400k said:
Did you find a label on it or did you have to remove the cover Jonathan?

I'm a little suprrised that a later model UK 960 Estate doesn't come as stock with some kind of differential anti-spin device fitted, G80 or otherwise.

I guess that one of those must now be very high on your wish list...I think it would make a huge difference to your car even before adding a supercharger.
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There was a label on it, I doubt Id be able to get the cover off with the rear subframe in place anyway so that saved a lot of work, good thing is once I get a hold of the guy in Dumbarton now I know I can check his cars on the off chance there is a 1065 in one of them just by looking underneath!
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Fingers crossed for you on that one. If your own 960 didn't have a G80, I don't know how common their fitment would be on other UK 3-litre IRS 960s?
 
Turbeam said:
Fingers crossed for you on that one. If your own 960 didn't have a G80, I don't know how common their fitment would be on other UK 3-litre IRS 960s?
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Spoke to a guy earlier who has got one so that is reassuring, not a priority at the moment but at least I know they are available
 
Just discovered that Japanese market got locking diff as standard equipment, have confirmed this on Japanese market 1995, 1996, 1997 960, 1998 S90 and 1996 940 brochure. So if anyone is struggling to find one, try looking in Japan!!
 
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