According to this weeks UK Autocar magazine....
Bugatti will cut the official top speed of its delayed Veyron to 350km/h(218mph). It follows rumours that the 8.0 litre W16 powered supercar was seriously unstable at high speed..... The firm is planning a special record-setting speed run to prove the original target (252mph) is possible.
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I always had the view that I would believe it was faster once I had actually seen it. Seems the F1 could remain top of the class for a very long time, although I am sure the Veyron could set all kinds of new benchmarks in 'special record-setting tests'.
Don.