Benefits of undertray lip?

[Vman455]

I happened to be looking at Porsche's website the other day and noticed they publish drag coefficients for their cars. The base 911 is Cd .29, and the highest-drag variant is the GT2 RS with a giant rear wing at .35.

One thing to keep in mind: sports cars have much smaller cross-sectional area compared to full-size trucks, and their total drag is much lower. That GT2 RS works out to about 0.75 square meter, while the lowest-drag RAM, the outgoing EcoDiesel quad cab, is 1.16 square meters.

[kach22i]

Originally Posted by Daschicken

How about the original acura NSX? Cd of 0.32. Not amazing or anything, but not bad either.

Looking back at other cars of that era, that was a darn good number.

The rear greenhouse C-pillar area reminds me of the GM EV-1 (Impact concept).

[gumby79]

Originally Posted by fastflyer

Other:

This flap is for lift but primarily to create high pressure on the front of the cooling stack. With a crude converging duct
I dont know what rig this is , duse it have a vent on/in the hood /finders ? Or dose the air pass through the coolers then dump back out on the pavement into the low pressure zone created behind the flap?
Aerohead you called it proformance orientated cooling at the cost of a front without holes . Add a lever turning the flap into a damper to close the opening and callit active aero. Or a temperature controled grill block.
----z

Kach22i Less blue area with a splitter, blue is lift from what I can tell - it has a negative number.

1 line above ⬇️

The underside of the splitter also generates low pressure (blue) and downforce

Under the splitter the blue is suction (negative numbers pull on a surface at a right angle ) toward the ground aka downforce. The bigger the gradient surface side to surface side the stronger the effect. The blue at the top of the wind screen on the lower example is suction toward the sky aka lift caused by separation resulting from too sharp of a radius (sudden 10-15°change of wind screen angle)
Dam Vs splitter
Dam has lots of blue (drag aka rear force) on the rear .

Splitter focused this drag energy into a smaller confined space, larger gradient and a different orientation now vertical and downforce. The blue also dissipated much faster returning to green (0 neutral) with the chin1/4of the rendering Vs 1/2 with the dam only.
Catch 22 your finger sliped I'm not ragging on you it just surprised me with your wealth of knowledge how much you've helped me with these things over the years. For you make the misinterpretation means we are human, it takes a computer to truly screw up.

[aerohead]

Originally Posted by Daschicken

How about the original acura NSX? Cd of 0.32. Not amazing or anything, but not bad either.

It would also be compromised for high-speed stability.Consider their Cd 0.10 Dream solar racers.

[aerohead]

Some of the early 1980s Pontiac Firebird, Firebird Trans Am, and Corvette, used the under-nose inlet.The development work was done at the Lockheed,Marietta,Georgia wind tunnel,using automotive clay mockups.
The sealed nose of the Trans Am version knocked 0.011 off the Cd.
All the cars had low ground clearance,and it wasn't uncommon to see the airdams sheared off.I used to find them in intersections with nasty dips.