Ford Escort ZX2 Aerodynamics

[BabyDiesel]

I'm starting a new thread here that will handle the aerodynamic aspects of my car exclusively

Here is some data on my car:

Stock Cd - 0.33, Ford ZX2 Automatic (2000)

Frontal area - 20.8 square feet, Ford ZX2 Automatic (2000)

Stock CdA - 6.9 square feet, Ford ZX2 Automatic (2000)

Stock Aerodynamic Resistance @ 62 m.p.h. - 15.8 kW/21.3 HPR, Ford ZX2 Automatic (2000)

Pretty good numbers for a 1998 car, but not good enough for us!

[BabyDiesel]

So far, I have added the following mods:

Wheel covers; the side skirts and air dam are no longer on.



Foglight hole covers




Front belly pan



Rear belly pan



Windshield wiper cover



85% grill block



Fender skirts



I do plan on making new fender skirts that extend to the rear bumper, as some members have. The sharp edge will promote cleaner separation.

[BabyDiesel]

I am planning on a kammback and eventually a boattail

Here is the template overlay -



For the front



I doubt that this is the proper way to go about a vehicle's front aerodynamics. I do want to improve the front aero, if possible.

[freebeard]

How is the wiper arm shield mounted?

[BabyDiesel]

Below the wipers, it is a tight space so it was originally wedged in place. A day of brutal crosswinds made me rethink that lol now it is held down with a few pieces of Gorilla tape.

[BabyDiesel]

Aerodynamic & rolling resistance, power & MPG calculator - EcoModder.com

I have been doing some playing around with this calculator. If my efficiency numbers check out, then I may have dropped my Cd down to the 0.28-0.29 level! That is awesome to me!

[freebeard]

Is it fixed to the hood or the cowl?

[BabyDiesel]

With more weight reduction, LRR tires, a Cd of 0.19, a drivetrain efficiency of .90 for a manual swap, and 77* air puts me at 70-80 mpg for my usual drive speeds of 45-50 mph (theoretically)

Aerodynamic & rolling resistance, power & MPG calculator - EcoModder.com

[BabyDiesel]

Originally Posted by freebeard

Is it fixed to the hood or the cowl?

Neither, it is fitted in-between hood and the wipers.

A picture may help to explain it better. I'll get you one tomorrow!

[aerohead]

Originally Posted by BabyDiesel

I am planning on a kammback and eventually a boattail

Here is the template overlay -



For the front



I doubt that this is the proper way to go about a vehicle's front aerodynamics. I do want to improve the front aero, if possible.

Eiffel and Hoerner both tested reversed streamline bodies ,and while the drag was higher,as half-bodies,and with wheels attached,I guestimate that you could see Cd 0.13 for a perfectly smooth wind tunnel model.
What we don't know,is if we can cheat on the windshield.If we can't,then the angles of the glass would make it impossible to see out of the car.
'Elliptical' bodies have the same drag as teardrop bodies,for the same fineness ratio,so I don't think you can hurt anything by extending the front.The pro's might say that you're creating undue additional skin friction.
Testing would tell.