CX of GT40

olfrjf · 10-12-05, 05:06 AM

Hi, do you know the CX of a GT40 (mine is a gtd40).

regards
Olivier

olfrjf · 10-12-05, 06:08 AM

Sorry, i speak about Drag coefficient in english....

regards
Olivier

olfrjf · 10-13-05, 06:47 PM

nobody for my drag coefficient? [img]/ubbthreads/images/graemlins/frown.gif[/img]

Alex Hirsbrunner · 10-13-05, 08:17 PM

Hi Olivier,

The Roaring Forties website lists the Cd of their cars as 0.35.

Regards,

Al

Mark Scrivener · 10-13-05, 10:31 PM

For grins check out http://www.answers.com/topic/drag-coefficient-1

It lists drag coefficients for several cars (but not the GT40). The Testarossa is 0.36 - close to the GT40. The Honda Insight is 0.25 and a 997 is 0.28, but the F50 is only 0.372. Of course cars like the F50 and 997 probably generate more down force with that drag than the GT40 does.

Mark

olfrjf · 10-14-05, 03:10 AM

Thanks Al & Mark,

regards
Olivier

theon · 10-14-05, 09:02 AM

Does anyone know the frontal surface area in order to calculate what I believe is called the drag area (frontal surface area X drag coefficient)? The GT40 may not have the best Cd but should have just about the lowest frontal surface area of any supercar.

Theon

Alex Hirsbrunner · 10-14-05, 10:33 AM

Hi Theon,

One way to *estimate* it would be to take a photo with a front view of 40 (there's a nice QTVR-like version here: http://www.roaringforties.com.au/showroom.html), draw a grid over it and count the squares that are covered by the '40. Then knowing that it's about 40.5 inches tall and 70 inches wide you can determine the actual size of the squares you used. Multiply the #of squares by the actual area of each square and you're going to be close enough for any kind of top speed vs horsepower calculation you are probably trying to do.

Regards,

Al H.

theon · 10-10-06, 05:15 PM

For anyone interested according to Kit Car Magazine the Superformance GT has a frontal surface area of 15.8 square feet.

Theon