Aerodynamics - Performance, and Economy?

[kickflipjr]

That Probe V is awesome.

I recently put a lip an the underside of my bumper. and I put tape over radiator openings. I don't think it is a good idea in the summer. But it is cool right now.

[Matt Timion]

Originally Posted by kickflipjr

That Probe V is awesome.

I recently put a lip an the underside of my bumper. and I put tape over radiator openings. I don't think it is a good idea in the summer. But it is cool right now.

I'm actually thinking of putting a front lip on my car as well. I'm keeping my eye open for one at the junkyard. If all else fails I'll just get the garden molding from Home Depot and do it that way.

[Matt Timion]

Below are pictures of the CRX MetroMPG mentioned above.

[SVOboy]

Me: Will a home depot lip work as well as a real one?
DrDisco: define "well" and "real"
Me: Will it do the same **** as one that I paid 50 for.
DrDisco: what did you pay $50 for?
DrDisco: the Si one?
Me: IF I paid 50 for one.
DrDisco: have you ever seen a home depot lip?
DrDisco: they are generally on the huge end of the scale
Me: I have.
Me: I'm just asking if it does the same ****.
DrDisco: the same as what though
DrDisco: Si lip?
Me: I dunno, a good one?
DrDisco: you're not helping
DrDisco: "good"?
Me: Si then.
DrDisco: i think a "good" lip is one that gives 500lbs of downforce
DrDisco: well then no, the home depot lip won't do the same thing
DrDisco: the Si lip doesn't do much more than look pretty, and block a little more air from getting under the car
DrDisco: with a bigass home depot one, you can do better at keeping air out
Me: I'm thinking gas mileage.
DrDisco: then you must weigh the gain of less air under the car to the drag of the lip
Me: So I have to think a lot.

Just talked the home depot lip over with disco. :/

[MetroMPG]

i did the home depot thing to a vw rabbit i had back in university. front AND sides. of course, i had no way to accurately measure if it helped or not.

i'm going to do a "lip" test when the weather warms up. of course aero mod results can't be generalized from one car to another... so i'm not being very helpful...

[GasSavers_BluEyes]

Originally Posted by MetroMPG

of course aero mod results can't be generalized from one car to another... so i'm not being very helpful...

Of course they can, generally . The principles of aerodynamics always hold true, and so as long as you don't expect to take your rear fender skirts off the Metro and put them directly on my LeBaron, it's fine.

Stuff like reducing airflow around the tires, limiting excess airflow through the engine bay and thinking long and hard before doing any mod that involves increasing frontal area. These principles will work on 99% of cars out there, so I think that's pretty generalized. Of course, how you implement them is vehicle-specific and the exact gains will vary but that doesn't mean that if you test something on your car that it won't help me figure out something on mine. Just takes a bit more thought is all.

Anyways, back to the original title - yes, aero mods have almost no downside. Weight is minimal if done well and depending on how far you take things it can be done very asthetically. Aero is also perfect because it benefits you no matter how you drive (unless it's all under 25mph). Cruise at 80? The % gain from aero improvements is actually bigger the faster you go so it's perfect for people who don't want to slow down much. As far as performance, I have noticed a definate improvement in passing acceleration since I've begun aero work on my car, so there's something there even for people who don't care about FE.