I'm currently preparing a car to run with the FFCS (hopefully) next year and have been eagerly absorbing everything I can find about the class and group. As a result, I've come up with a question that I can't find satisfactory clarification on. Am I reading the rules wrong or do they allow for CF and PCF cars to run bodywork that is in no way related to original manufacture? So long as the new body isn't perceived to provide additional downforce over the original one, the cockpit opening conforms to the rules, the maximum height/width/length dimensions are conformed to, and it isn't made of "advanced materials", I see nothing preventing it. There are no "original specification" provisions for bodywork except for HF. This seems like an intentional difference, since at some point it was deemed section D12 needed to exist. I can't be the first to notice? Of course, this is all theoretical until someone jumps the shark and goes crazy with CFD*.
(* maybe not so crazy, since it appears you can download free computational fluid dynamics software nowadays)