You wouldn't normally associate vinyl roofs with race cars but that was exactly what happened in the US Trans-Am series. At the start of the 1969 season, Mark Donahue fronted with a Penske Camaro fitted with a vinyl roof which caused a huge stir. Rivals claimed the car had been left in the acid bath too long to lose some weight which had caused the roof to buckle, so Penske had covered it over with vinyl to cover it up. Some rivals even thought the vinyl provided some sort or aerodynamic advantage! Race officials had no choice but to demand its removal to stop all the innuendo. The following year Sam Posey turned up with a vinyl roof on his 1970 Dodge Challenger and faced the same accusations about acid dipping, only this time Posey's team got busted. After the roof buckled when an official leaned on it, it was ruled illegal and the team had to gas-axe a standard roof off a brand new Challenger at a local Dodge dealer to be able to race!