ZX2 EVO bumper: How will it affect aero?

[BabyDiesel]

I happened to find a body kit on Craigslist for the Escort ZX2

escort zx2 ground effects kit



I originally wanted just the side skirts, but the more I have looked at the kit and talked it over with members on teamZX2.com, the more it has grown on me. But since one of my goals is sub-0.20 Cd, I do not want to do anything that will negatively affect me.

So how will this kit affect the aero? I would think it would increase the frontal area and increase downforce, but I don't want to jump to conclusions yet. That's why I'm coming to the experts

[freebeard]

It would be easier to assess from a picture of it installed on a car, but I'd say it all depends on what is happening behind the openings and underneath the car. For instance trim back the underlying sheetmetal and have air curtains in the front wheel wells. And a diffuser in back.

I'd put chrome bullets in the light buckets, like a '56 Caddy.

[BabyDiesel]

Freebeard, here is how the rear will look:




and the front:




They would have full aero treatment, not limited to grill block, belly pan, diffuser and air curtains, etc

[freebeard]

I'd never have guessed the skegs behind the rear wheels, for instance. I'm not sure what's optimal there, you see some ka-razy stuff on race cars. I'd go for a spat that is 'flat' on the outside and curved divergently on the inner side. Combine the three openings into one. What's ahead of there, gas tank or spare? That's aerodynamically valuable space.

On the front, I understand that air curtains are a convergent duct that shrinks from whatever opening is available to a tall, narrow slot pointed at the face or tread of the center half of the front tire (ignoring the top and bottom quarters). This is not that. There is an example that floats around of an external duct air curtain.

Do you need the driving lights? You could make bullets from recycled dining-room light fixtures.

Active shutters in those three center openings. P-51s had their shutters on the exhaust side, but it's hard to do a walk-around inspection on cars, so for seviceability, shutters on the intake side.

[aerohead]

I wouldn't recommend you use any of it.If you were doing 24-hours of Daytona,or LeMans I'd say different.But I don't see low drag anywhere with that stuff.
PS a single opening would be the ideal

[freebeard]

aerohead's too modest to use his own T-100 as an example. Here's the Stupidbaker in the A2:


http://bangshift.com/bangshift1320/watch-incredible-stupidbaker-land-speed-car-get-wind-tunnel-tested-a2-wind-tunnel/