ORIGINAL: da Rock
Mention has been made a couple of times about the race car the Petty's ran that had a vinyl top.
Both Richard and Kyle have told the story of that car in detail. It was at a time when the teams were acid dipping the car bodies to reduce the weight above the CG of the car and that was part of the whole story. It was also at a time when nobody had much understanding of aero.
They did not do the top that way for aerodynamic reasons. Their ''punch line'' is that in fact the vinyl came loose and blew open in front. They chuckle about the irony of that.
Actually, a piece of debris hit the top edge of the roof and caused it to buckle, then the air got under it and made it worse...it wasn't just the vinyl...nor was it the fact (? ) that the sheet metal was thinner than stock. I have the race on video...Richard gets up on the hood with a hammer and beats the #$%@ out of it...then takes an awl and punches holes, then wires the metal back down to the roll bar hoop at the top of the windshield
It's been on "The Glory Days" with Dave Despain on Speed Channel and whatever the name of that channel was before they changed it to "Speed"...might have been ESPN, back in the 80's.
I remember reading an article in (I think it was ) Hot Rod magazine written at the time, by the Chrysler engineers about the theory of the surface roughness and boundry layer, etc. trying for some kind of edge to help get them more competitive on the faster tracks.
Ya gotta remember that they (Chrysler ) had dominated in '66 and '67 but when Ford and Mercury introduced the fastback Torino and Cyclone, they (F & M ) slaughtered everyone in '68 and '69, setting speed records, and winning the NASCAR championship both years.
Richard Petty left Plymouth for Ford in '69 because the '68 cars were so uncompetitive on superspeedways. That's why Chrysler came out with the Plymouth Superbird and Dodge Daytona with the pointy beaks and 2' high wings in 1970.
The Mythbusters used the same car for the entire series of tests...
Check out the Discovery channel web site...you can visit the Mythbusters forum and ask them yourself if you want.