Grrr wet understear

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Nearly plonked the e36 into railings trying to take a tight near 90deg left turn at 10mph (?) on the way back to work.

I felt it slip on initial turn in, then grip caught and I thought I was ok.. put foot down gently (!) and it started to go way more sideways than I thought possible given tyre dimentions, it slid sideways another meter, maybe half, towards the railed traffic island. Completely stopped then pulled away.

It must have looked like I was driving like a tool to the traffic sat, but really I've taken corners quicker in a micra.

It wasn't completely aquaplaining, but it sure felt like it. The tyres up front have loads of tread, but are called tiger, or killers or some other cheap rubbish. I will replace them if it happens again but..

Is there a name or term for bmw and mercs with suspension which change camber angle on cornering? ie to help high speed cornering. Does this effect slow cornering much, or have I just been a ****?

/concerned
 
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My first instinct would be the tyres (assuming there's nothing obviously wrong with the car) but don't rule out diesel spillage too.

Cheap tyres on a BMW can mean insta-death. When I first got the 8 series it had some of the original Pilot Sports on it (horrendously hard/guff tyres), maybe 3+ years old and plenty of cracks in them. I could pirouette round roundabouts without even trying and ended up looking like a right eedjut on several occasions.

I found it worst when it had been dry and there was some light rain and it effected both ends of the car.
 
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My first instinct would be the tyres (assuming there's nothing obviously wrong with the car) but don't rule out diesel spillage too.

Agreed!

Tyre's are definitely first port of call.

Would also be worth having someone take a quick look at suspension too.

I have two experiences

1) The inside of my Shock arm was wrecked (1 in million chance) caused me to slide out at 40mph and end up in a hedge!
2) My Clio 197 CUP Edition, Front passenger suspension had faulty "o" ring!!!! Told it was 1 in a thousand chance but i had it and could have been bad. results.
:) my 2p worth
 
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All depends doesn't it, damp conditions + oil soaked into the road which is now lifted = going sideways, little bit of damp or poor tarmac = going sideways, fuel spill = going sideways.

I went drifting in the Passat a few weeks back on a damp road round a tight bend that i've taken millions of times in the past at quicker speeds.
 
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Is there a name or term for bmw and mercs with suspension which change camber angle on cornering?

ALL cars do this to some extent, it's caused by a combination of the castor angle and the "steering axis inclination" (SAI). Camber also changes with body roll to some extent (unless you have a live axle).
 
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Just pop the clutch and give it some throttle, should counter any understeer issues you have ;)
 
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ALL cars do this to some extent, it's caused by a combination of the castor angle and the "steering axis inclination" (SAI). Camber also changes with body roll to some extent (unless you have a live axle).

Thanks for the explanation! :)

Yes I know the tyres are cheapies, stuck toyo's on the rear last week ordered another two last night. Lost confidence in the fronts now! :p

Took it to a unused carpark last night and ran passed the same corner a few times, couldn't quite replicate it but there is a certain angle where I do seem to be slipping/stepping out.

If the new boots don't sort that, I'll get the front checked out when its at the garage this week. Although it was stuck on a hunter alignment last week, the fronts were pretty much bang on. Who knows..
 
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You have ditchfinders on, they are called this for a reason, glad to see you're changing them.

Beyond that, alignment, worn suspension etc could be the cause, but my money would be on the tyres.
 
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ALL cars do this to some extent, it's caused by a combination of the castor angle and the "steering axis inclination" (SAI). Camber also changes with body roll to some extent (unless you have a live axle).

King Pin Inclination (KPI) is the generally accepted term ;)
 
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You have ditchfinders on, they are called this for a reason, glad to see you're changing them.

Beyond that, alignment, worn suspension etc could be the cause, but my money would be on the tyres.

They are good in dry, its the first real wet day I'd had in the car yet and my face just dropped like this - :/

Both wishbones have been replaced, but the steering feels too reactionary (is that a word?) to the road. Something perhaps not right but I'm getting the suspension looked at / overhalled this week as I have big plans for the shell!

Well big, meaning a proper 6 pot. :p
 
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i suspect it might be your cheap tyres ;)

THIS.

On my e36 with random brand tyres I was driving in the damp (misty rain, so wet road, but not standing water or raining) went round a sweeping corner at ~40mph on a 60 limit road and the back end stepped out!

I put on decent tyres and could take that corner (and many other harsher ones) in the wet (raining, standing water etc.) and the back end stuck to the road.

Never had understeer in the BMW though...but I guess I had worse tyres on the rear than the front. :p I also changed the tyres as soon as I could after that moment. :p
 
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^ It was a mist wet day, hadn't rained but drizzled all afternoon. Although cheap, the front two have thousands of miles worth of DRY miles left on them.



With ease it would seem..

You can't guarantee it will be dry, and that sort of wet weather performance sounds downright dangerous. Bad tyres (because not all bad tyres are cheap) are false economy.
 
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You can't guarantee it will be dry, and that sort of wet weather performance sounds downright dangerous. Bad tyres (because not all bad tyres are cheap) are false economy.

Mate, you don't have to tell me that, I live in SCOTLAND! :D

No I agree completely, got another set of toyos coming.

Its a shame that these bad cheap tyres that actually do well in the dry are a complete liability in the wet. But hey, I didn't buy or pick them but can easily replace! :)

Its more the suspension, the more I'm in it now more something up front doesn't feel right. Its in for RTAB's and polly's this week, I'll get them to gander at the front.
 
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