Unsettled under braking

[Penfold1977]

Just been to Brands in the 'new' car (a '99 306 Rallye)

The car was really good fun, with loads of grip and in general very well behaved. However, whilst under heavy braking, the car seems to squirm (sorry if I don't have a better way of describing it) If I really stand on the brakes, the car becomes unsettled.

What could be the cause for this? I was running in slightly taller tyres (50 profile instead of 45) then in the 182, which didn't suffer this. Is there a big enough difference in tyres to cuase this, or could it be something in the suspension setup, which is still standard.

Cheers in advance!

 

[edde]

I'd have the tracking checked.
How do you mean unsettled though does the back get light or just one side which might show the brakes as the problem.
Depending how you drive can have a huge influence though mine can get a bit loose at the back under serious lock up on the brakes but that due to a soft standd suspension setup my Williams is much harder suspension I cna lock up complelty in a dead striaght line from well into 3 figures no problems.

 

[Penfold1977]

I had the tracking done a couple of days before I went out on the track, so I'm pretty sure it's not that.
As for what happens, the just doesn't seem to brake in a straight line, it feels a little like the back end is trying to break away or that it's rocking as the side walls to the tyres give. It's very hard to describe.
I think it's something in the suspension that might be worn, it's been suggested elsewhere that it's the bushes and they might be worn.

I might have a clip of where I got out of shape going into Paddock Hill, which might help describe the issues. I'll have a look tonight.