Bugatti's Veyron Super Sport has been stripped of its title of fastest production car in the world.
In confirming its decision, Guinness World Records said it discovered that the car used to set the world record of 431.072 kilometres per hour had been modified and as a result it had breached the rules.
In today's Sunday Times in the UK, the paper claimed a speed restrictor on the Veyron had been deactivated - something which Bugatti doesn't deny - on the record-setting car in July 2010 which is seen as a key difference from the 30 cars sold to public.
''It has come to the attention of Guinness World Records that there was an oversight in its adjudication of the 'Fastest production car' which was set in 2010 by the Bugatti Veyron 16.4 Super Sport,'' Jaime Strang, GWR's PR director, said in a statement to the paper.
''As the car's speed limiter was deactivated, this modification was against the official guidelines. Consequently, the vehicle's record set at 431.072 kmh is no longer valid.
"Following this, Guinness World Records is reviewing this category with expert external consultants to ensure our records fairly reflect achievements in this field.''
GWR's rules state that the car that sets the record must be mechanically identical to those on sale to the public. The speed restrictor on production Veyrons apparently lowers its top speed from 431kmh to 415 kmh - for safety reasons.
The issue came to light last week when US sports car maker, Hennessey, questioned the Veyron's claim, pointing to the restrictor and claiming its own Venom GT was actually the fastest after it posted 427 kmh at a US Naval air base in California recently. That record, however, was not set under official world record conditions which require an average speed to be set over two timed runs.
Before the Veyron was crowned fastest production car, Shelby Supercars in the US held the record with its Ultimate Aero and a speed of 412.153 kmh.
Bugatti told the Sunday Times it was standing by its world record and it would be seeking clarification.
''Guinness knew the Veyron's speed limiter was deactivated but that for safety reasons, cars subsequently sold to customers would have their speed limiters activated [set at 415 kmh].”
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