Guinness has apparently stripped the Veyron SS of its title as the report – as well as Hennessey's claim – says that the standard production version of the Veyron SS has its speed limited to 258 mph, but this was altered just for the test to pick up the extra speed. The rules for the record indicate that the record-setting car must be unchanged from what is available to customers. Since the Venom GT's record is still unofficial, the world record for fastest production car reverts back to Shelby SuperCars (SSC) Ultimate Aero with a top speed of 256.1 mph.
In order for the Venom GT to take this title from the Ultimate Aero now, it must attain its average speed over two timed runs. Perhaps more importantly, Hennessey must also build some fifty identical examples of the Venom GT in order for it to qualify as a "production" car. In the short term, at least, that might end up being the taller order.