What month in 73 did 74 model year production begin, What month in 73 did 74 model year production begin? Options

[Brisco914prc]

Is there any published information regarding what month in 1973 the 1974 model year production began? Brett Johnson's 914 Authenticity does not contain that information.

My understanding is that in that era, and earlier, Porsche typically began production of the new model year after the August vacation period. So that would mean that 1974 914 model year production began in late August / early September.

I'm interested because there is a 914 built in July 1973 that has a 1974 rear bumper on it (the style with the two rubber bumper guards). My assumption is that is not the original bumper to the car because a July 1973 car should be a 1973 model year 914.

The car does not appear to show any rear end accident damage or repair that would have caused the original bumper to be replaced. But of course I can't be sure of that.

thanks,