View Single Post
panzerfaust panzerfaust is offline
Registered
 
Join Date: Jan 2012
Posts: 1,118
Quote:
Originally Posted by Highway-Star View Post
Here are a lot of Porsche -models drag-coefficients:
CW-Werte Porsche-Typen - Forum: Porsche Fahrzeugpflege von PFF.de

But one value for all 930 LOL
Quote:
Originally Posted by Noah930 View Post
OK, I still don 't know the right answer. Does anyone have Paul Frere's book on the 911 Turbo, or Karl Ludvigson's Excellence Was Expected? But I looked at Paul Frere's Porsche 911 Story and got these figures:

The 934 had a Cd of 0.44
The 935-76 was 0.435

The H-series Carrera (I took it to mean narrow body) with front air dam & rear spoiler was 0.414
The H-series Carrera without aero aids was 0.423

The use of American market impact bumpers raised the Cd from 0.40 to 0.42. While Frere was not very clear to which 911 variant he was referring, the context seems to suggest that it's the narrow body car, not the turbo body. Still, if that's the Cd of a narrow body car, the Cd of a turbo body must be worse.

The 964: 0.32
The 965: 0.35
The 993: 0.33
The 993tt: 0.34

Edit: another book I have, Randy Leffingwell's Porsche 911: Perfection by Design lists a 1983 Carrera with a Cd of 0.40.
As you can see the minimal drag cd improvemenst with the 934 vs 935-76. What would be really interesting is the difference with the center of pressure. Going slopenose by having the pontoon fenders off as well as the larger verticle wing supports would drastically move the center of pressure rearwards for high sport stability
Old 01-14-2017, 11:17 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #13 (permalink)