[aerohead]

I ran three iterations until I got a data fit.
The relationship to the 'RACE' version of the Plymouth Road Runner:
*It's drag is 13% higher than Daytona 500 = Cd 0.316
*Nose and airdam = delta-Cd = 0.046
*Flush windshield,A-pillar fairing,flush side glass = 8% delta-Cd
*Semi-fastback = 11% delta-Cd
-----------------------------------------------------------------------------
Starting at Cd 0.316 and using -0.046 for the nose/airdam improvement (published),I solved for a Cd which with an additional 8% and 11% delta-Cd increment reduction equaled Cd 0.316.
I came up with Cd 0.447
I'd sure like some other members to run the numbers and see if we get an agreement.
--------------------------------------------------------------------------
Also,I did the same thing with the 1968 Dodge Charger and came up with a 'civilian' version of Cd 0.416.
--------------------------------------------------------------------------
Here are some Cds of this time period:
1960 Plymouth....................... = Cd 0.48
1960 Ford Falcon................... = Cd 0.419
1963 Ford Fairlane................. = Cd 0.54
1964-1/2 Mustang notchback.. = Cd 0.475
1968 Ford Galaxie.................. = Cd 0.421-0.436
1968 Falcon Futura................ = Cd 0.416
1968 Buick Special................. = Cd 405
1968 Oldsmobile Super 88......... = Cd 0.421
1969 Dodge Wagon................ = Cd 0.587
1969 Oldsmobile Toronado....... = Cd 0.38
1969 Corvette...................... = Cd 0.39
1970 Dodge Polara Hardtop...... = Cd 0.499-.498
1970 Citroen GS.................... = 0.37-0.38
1970-1/2 Camaro................... = Cd 0.491