The handling on the Cavalier is weird:
At normal (not on the limit) road speeds, it's fine. Predictable, quite direct steering, with good feedback through the wheel as to what the front tyres are doing.
Past that limit though, strange things happen.... I think the tyres (195s Avon/Cooper) give more grip than the (120k mile, still original) saggy Vauxhall suspension can take. Take a nice fast roundabout as an example. You can push and push and push and the front will just try and cling on, but steer a bit tighter (getting more angle out of the fronts), and the back sort of jacks up and over the loaded rear wheel. Instinctively, you back off the throttle and the steering then goes light then there's not a lot you can do other than wait for the car to settle back on it's springs with a huge, ungraceful wobble and a sag once you're not cornering too hard anymore.
If on the other hand, you keep your foot in it, you end up in some weird front understeering, back trying to oversteer, and sagging all over the place... If you try and change direction, it will just wallow...