weird story about vt-vz wagons spinning out?

[Adds_05]

OK so Ive been told a story from someone i know who is pretty knowledgeable about Holden and cars in general.
The story goes along the lines of,when the vt wagon was being built,supposedly if they got to about 160kms/h,the back end would basically get the speed wobbles and it would cause the car to spin out etc.
He tells me that he read it in a book somewhere a couple of years ago and he's not the type of bloke that talks shit/would make it up but Ive never heard of it before?
obviously they would have fixed it for production some how and im sure there's people on here that have been faster than that in their wagon and haven't spun out...
has anyone else heard of this before?

[Calaber]

I somehow doubt this story. The VT was an Australianised version of the Opel Omega, which had been in production for a couple of years before the VT was released. As the basic rear suspension and underbody were the same, I imagine that any undesirable traits like this would have been detected during development of the Opel.

[ari666]

any risk of fatal accident gets added to the recall list:
http://www.recalls.gov.au/content/in...mItemId/952855


there is a rumour that auto makers have a calculation about risk vs the cost of a recall, (which was true in the early 70's) but i can safely say that is not true in australia.


edit: hmmmm http://www.recalls.gov.au/content/in.../itemId/955699

[Reaper]

My father had a VTII Berlina wagon, I drive a VY Exec wagon at work on occasion and my wife has a VZ SVZ wagon which is a pretty comprehensive spread of that range. I've had them up to 140 km/h a few times and all of them have been rock solid. Never heard any stories of them getting the shimmies. All I can suggest is the shocks and suspension was completely stuffed which might cause such a thing at high speed on crappy roads.

Reaper

[Adds_05]

My father had a VTII Berlina wagon, I drive a VY Exec wagon at work on occasion and my wife has a VZ SVZ wagon which is a pretty comprehensive spread of that range. I've had them up to 140 km/h a few times and all of them have been rock solid. Never heard any stories of them getting the shimmies. All I can suggest is the shocks and suspension was completely stuffed which might cause such a thing at high speed on crappy roads.

Reaper

This was supposedly during testing before the vt was released, so i guess it could be a case of testing with stuffed shocks to see what would happen but i guess they must have done something to avoid it.

[Drewie]

We did a trip to the NT on the Ghan in 2004 and hired a VY Wagon in Darwin to do some touring, this was before the 130 kph speed limit was introduced so there was no speed limit then, the distances in the NT are huge when travelling but the roads in places are gun barrel straight, we had the VY wagon cruising at 150 kph for hour on end and it felt rock solid, I don't know if it is their roads up there ie the camber etc but I felt more secure at 150 kph on those roads than I do on the Hume at 120 kph, but getting back to the original question the VY wagon we hired was extremely steady at high speed, never had one moment where it felt funny.
Being 2004 it was a pretty new car at the time.

[ari666]

Being 2004 it was a pretty new car at the time.

and not a vt...

[Drewie]

and not a vt...

I was going by what the thread was called!.... "weird story about vt-vz wagons spinning out?"

[ari666]

i realise just after i posted soz

[Adds_05]

just to clarify,im meaning before the vt went into production, so during testing etc. probably shouldn't have put vz in the title...

[HoZy]

I know a mate, That bought a V6 VT wagon, Transplanted gear from a wrecked VZ maloo ute, an It's been well above 160... No "speed wobbles" An that's throwing lots more power than any VT had from holden.

Cheers
Mat

[Adds_05]

yeah i found it a bit hard to believe but this person that told me swears black and blue it was written in a book he had a read of.

[som]

i haven't read that but i did read in a road test some time ago about VT's "self steering" from the rear as they got a few kms on them due to the fact that the control arms bent giving them excessive toe in.apparently the lack of a toe link added to the problem.as we know changes were made to the VX II and again to the VY.

[TMM]

Commodores tend to oversteer around fast sweeping bends. Probably because the amount of caster they run provides lots of dynamic camber and grip to the front end when driving around a corner. It's worse on wagons and utes because they have stiffer springs in the back which biases handling more toward oversteer.

As the basic rear suspension and underbody were the same, I imagine that any undesirable traits like this would have been detected during development of the Opel.

The Opels had the toe link but for whatever reason Holden decided to delete it when building the Commodore (to save costs?). That back fired big time when people discovered the less then desirable tyre wear and handling characteristics.

VT and VX1 are more unstable then the later models because of the lack of the toe link. The toe links job is to keep the toe to a minimum as the wheel moves up and down. VTs also tend to have more camber which compounds the problem - more camber gives more grip on the outside tyre, but less on the inside tyre, so the rear will be 'steered' by dynamic toe on the outside rear wheel.

Also fwiw:
When my VY was on stock FE1 springs/shocks it felt very nervous at anything over 120km/h, you'd have to concentrate pretty hard just to keep it in the lane. Replaced all the bushes in the front end and got a wheel alignment, it didn't change one bit.

Now it's on Kings HD Lows and KYBs, it's completely stable at 160kmh. I guess the old (130,000k) springs and shocks just weren't up to the job!

[Calaber]

Yes, I knew about Holden deleting the links - that's why I said the Opel had the same "basic" suspension - I was implying that there were differences. And yes, it would have been deleted on cost grounds - typical of Holden around that time. (Finally putting them in on the VX II gave them something to boast about as if it was revolutionary!) It's not so much the toe-in or out that the links control - it's the excessive negative camber under load, and even unloaded when the springs got tired, which caused such excessive inner tread wear.

In theory, negative camber should assist with cornering but just having heaps of it on the rear end, without proper control, is a furphy. Negative camber is of more assistance to the front wheels during cornering. Your point about "more camber gives more grip on the outside of the tyre" is not quite right. In the straight ahead direction, the load is obviously on the inner half of the tread, not the outer, so the inner tread is doing all the work - hence the rapid wear rate on VT rear ends. When cornering, the camber enables the roll movement of the body and suspension to keep the tyre more upright under load, thereby ensuring that the entire tread remains parallel with the ground and providing greater grip, rather than "rolling under" and tearing the tread off the outer shoulders. Unfortunately, because the VT-VX I lacked the links, the rear suspension suffered from excessive "squat" and lacked the controlled movement that VX II's and later have.

[ari666]

Holden

repost my link, in case people missed it.

having the rear trailing arm come off at speed would certainly not be fun.

[TMM]

Yes, I knew about Holden deleting the links - that's why I said the Opel had the same "basic" suspension - I was implying that there were differences. And yes, it would have been deleted on cost grounds - typical of Holden around that time. (Finally putting them in on the VX II gave them something to boast about as if it was revolutionary!) It's not so much the toe-in or out that the links control - it's the excessive negative camber under load, and even unloaded when the springs got tired, which caused such excessive inner tread wear.

So true about Holden introducing 'features' slowly as to justify updated models. I think i've read that the toe link didn't do much to help the camber problem, it was more the revised subframe/arms (VXII and again for the VY) and bushings. HSV retrofitted the toe links to the VT, and they still had shed loads of camber.

In theory, negative camber should assist with cornering but just having heaps of it on the rear end, without proper control, is a furphy. Negative camber is of more assistance to the front wheels during cornering. Your point about "more camber gives more grip on the outside of the tyre" is not quite right. In the straight ahead direction, the load is obviously on the inner half of the tread, not the outer, so the inner tread is doing all the work - hence the rapid wear rate on VT rear ends. When cornering, the camber enables the roll movement of the body and suspension to keep the tyre more upright under load, thereby ensuring that the entire tread remains parallel with the ground and providing greater grip, rather than "rolling under" and tearing the tread off the outer shoulders. Unfortunately, because the VT-VX I lacked the links, the rear suspension suffered from excessive "squat" and lacked the controlled movement that VX II's and later have.

Ah i meant the outside wheel, I should've worded it better. I.e. when you are going around a left hand bend, some camber on the right wheel will help it sit flat with the road, but the left wheel is cambering the wrong way, making it have less grip then if it were aligned to 0º. So the rear of the car will just travel in whatever direction the right wheel is pointing. On bump the wheels toe in, and on drop they toe out. If the road is undulating it can make the rear of the car wander around as the toe changes. If the toe is severe enough it makes the car fishtail in a slide because you get a pendulum effect where the rear wheels are constantly trying to (over)correct the slide. If you've ever got your Commodore in a slide you've probably noticed that you don't need to countersteer as much as you would expect for the rear to come back into line

[Calaber]

If you've ever got your Commodore in a slide you've probably noticed that you don't need to countersteer as much as you would expect for the rear to come back into line

Nah, I'm an old fart when I drive. Never go fast enough to get myself into a slide, even in the wet. I've always found my VY to be very stable and secure in cornering but I tend to drive within my own capabilities, so the car is never really placed in a situation where a slide will occur. Of course, this doesn't mean I won't ever experience a slide - always the time when oil or somesuch on the road is going to throw a spanner in the works.

I remember encountering tailies in the old VR though - it was definitely tail happy, particularly on roundabouts. The VY is a far more stable and safer vehicle in corners than the VR ever was.

Just a side issue - regarding Holden's updates to justify new models. I've always believed that the VT II and VX II were models that should never have been released, because the advancement in engineering from VT I to VX I was virtually zero, if you discount the introduction of the Gen 3. The VT I should have gone straight to VX I, with the Gen 3 introduced on the VX and the proper rear suspension on the VT. Just my personal perception, anyway. As it is, they sold heaps of all those models and made a motza, so who am I to dispute their marketing prowess?