Unstable car under braking?
 

I was "making progress" down my private road last night in the TVR, going a little quicker than usual. I noticed that when accelerating over the rough road, the car felt nicely composed, but when I eased off (engine braking is very noticable on the TVR) or braked, then the car was unstable and took some holding on the road.

I'm at a loss to explain why this should be so.

On smooth roads, it's always very composed no matter how fast you go, so I guess it's suspension geometry or spring/damper rate related?

Any help appreciated.

There are a couple of things I've found that can cause this. Geometry settings and worn tyres. May be worth looking at these first.

Have you tried the tvr bbs as this may be just the way it is normally?

Dave.

I have driven 2 TVRs (a 350i and Chimera 4.0) and they both felt light as you lifted off and squirmed quite a bit under braking.

I think it's an inherent 'feature'

Andrew...

So TVR's have a 'feature' designed to throw you off the road, cool :) One way to keep your attention focussed on the road :D

Dave.

seperates the real drivers from the pretenders :D

agreed with Andrew, most "sports" production cars feel light when you lift off after reaching a "good" speed

I think its the compromised suspension(preload/damping rates), they have to be designed to cope with the ride around town and trips to Tesco's as well more enthusiastic driving..after a few years wear and tear, its even worse

I think you'll find it's to do with weight transfer under heavy braking. The rear goes light and the car becomes nose heavy and is therefore effected more by camber and uneven road surfaces. What the weight distribution is the TVR in questions this could be compounded by worn suspension and steering bushes ?

Mark A

Could be Shocks had the scoob do exactly the same when the shocks went. New ones fitted now and no more snaking!:)

Shocks and tyres were new only a couple of thousand miles ago. It may be the bushes beginning to give up though, so the toe changes under braking?

Weight distribution is about 50/50 IIRC and the car doesn't "dive" under braking, so I expect the brake balance is more or less OK.