Hi all

I took my car out for a bit of a blat today despite the strong winds, and found that with a rear crosswind (coming in about 45 degrees to the back end) the car was unbelievably twitchy... (that much so I was going round corners at about 40 which I would normally do at a very law abiding 60). Does this sound normal? If not any suggestions as to how I can remedy it?

Thanks

Mark

How's your toe-in?

If it's a bit toe-out it can be quite unpleasant, and if it's straight-ahead then it can be variable according to conditions.

Ahhh, you may have hit the nail on the head there...

I will get a friendly garage to check my tracking for me.

Thanks!

It may help to rake the ride height ie set the front ground clearance slightly than the rear.

Wider rear tyres

Get them to check your castor too!
(off to get the popcorn! )

Extra castor or trail will actually make it worse.

[Edited on 2/3/08 by britishtrident]

I am not suggesting extra castor, I am suggesting that there is some and that it is the right amount!
(at the front of course!)

[Edited on 2/3/2008 by nitram38]

Given that you mentioned the strngth of the wind, my first thought would be aero effects, rather than mechanical, as surely you'd feel them all the time?

From an aerodynamic point of view, the lift of a road car can increase dramatically in sidewinds, sometimes to 5-10 times the straight-ahead value. On top of this you get lateral forces trying to roll and twist the car - all of which can combine to give very twitchy and floaty feelings, especially at the rear.

In terms of remedies, it's hard to give general guidelines so can you post a pic of your car? Otherwise all you can say is "sharpen any rounded corners at the back', which isn't always possible nor the best route. Sorry :s

There's one thing you might like to look at - the ride height. These cars can be 'difficult' if you set the front higher than the back - they like to be up at the tail a bit, even if it's just an inch higher.

I took the car out again today (not so windy) and noticed that the steering didn't feel quite right (even though there was not a lot of wind) so I gave in and took it to the nice men at Kwik Fit. The Toe-In was about 4 degrees (must have been caused by me stripping, greasking and rebuilding the suspension) so I had this dropped back to 0.5 degrees and it felt considerably better!

I will check the ride height over the weekend (if it stays dry) but I am fairly sure the back is a little higher.

Mark
(now feeling dim for not guessing I may have affected the geometry)