Start with the belly pan for the biggest gains. Look at Keeps on Rollin' - basjoos. There's a thread around here somewhere showing his transformation. Search the archives. He went from high 50 to high 60 and 70 with aero mods. With a good belly pan an airdam is not much help. I know on my car, CD .33, a full airdam decreased FE by .9 MPG. Only after cutting out all but the area around the tires did it come back to a no loss situation.
Well, I need to get the materials for the bellypan real cheap for it to make economical sense as I see it. Hopefully I'll be able to get enough material to make a front grill cover (currently its about 6 sq ft of race tape), rear wheel skirts, wheel covers, and side skirts. If I ever get the material, I'll remove my front end cover after making a pattern, and make a test run for MPG before adding the aero stuff, and than make another MPG test run after its all installed, hopefully under similar weather conditions.
As a separate issue, I'll probably check into whether the newer, more aerodynamic trunklid would fit my car and what one would cost. Thats likely not a paying proposition, though.
I do my own mechanical work and the last thing I'd want would be to have to remove shields to get to things that need to be checked or repaired.
My fender skirts are a pain as far as checking tire pressures if chance doesn't put the air thingamabob where I can get to it.
Also...cars are designed for a lot of airflow around the trans...exhaust...and diff (if rear drive)....for cooling.
So a compromise might be an air dam at around the same ground clearance as the rest of the stuff under the car...can't say how it affects mpg though.
Another thing (might have mentioned this before ;-)).....covering extra holes in the front and covering the gas tank area at back likely could be just upping operating and fuel temps...which will improve mpg.
Leading the perpetually ignorant and uninformed into the light of scientific knowledge. Did I really say that?
a new policy....I intend to ignore the nescient...a waste of time and energy.
Everyone is correct : there is not much to be gained...
Now that you've jacked around with aero mods, tire pressures, "trim tabs", belly pans (what a pain!), and all this "Tornado" rubbish...let me just say: Have you thought about modifying that stuff in your gas tank? It used to be known as "gasoline"...but, lately it smells funny (like 3-in-1 oil?), if a bit is spilled while refueling / pouring onto a smooth concrete surface...it's still damp hours later! The gasoline of yesteryear would have evaporated in a few minutes! This is the stuff your engine is supposed to run on ??? Ah! the 21st century!
Can the gasoline be changed? Cheaply? Safely? Legally? You bet!
Just as soon as Matt Timeon sends me an SSAE with his address, I'll send him info you'll be able to see , once posted by Matt. -Ted Hart
Nothing alone is going to give you a huge jump in %. There is also a ceiling....
Sorry about the "zip" typo...but I thought I'd leave it alone! LOL?
You say "Nothing alone will give you a huge jump in %." You were talking MPG, yes? If Matt ever posts my run sheets...I will show you how to achieve a minor miracle.
What you do is ... increase the torque output of your engine (at the same throttle setting). Then, watch your mileage soar! It's about the efficiency of conversion of the energy in gasoline to mechanical energy (torque).
Looking at the conversion picture from another direction... have you notice the MPG rise (on a MPG gauge of some sort) when you lift your throttle foot just a bit? Same thing! Lower the load, MPG goes up.
Today's gasolines are not going to make the power (torque) of yesteryear's gas ... so, you're not gonna get the torque to generate the potential mileage
in a gallon. If the gallon is not burned "properly", less MPG is delivered.
Thus sayeth the "magic bullet"... under the ceiling!
One thing I noticed today when my Daughter came home with the 99 was that my 97 is missing the front air dam. The reason I haven't tried a belly pan is because the friend that works at the place that makes thin aluminum sheet stuff hasn't gotten me any, yet. No, I haven't tried rear wheel skirts, yet, either, again due to lack of materials. But given that the aero mods up front "should" have given me at least 1 mpg, I don't have much faith that rear wheel skirts will give me much either. To be honest, from what I've seen thus far, I found no measurable gain at all from smoothing the whole front end airflow wise by eliminating most of the holes and protrusions, including windshield wiper removal. The impression I've gotten from it is that it must not be making much improvement in the drag coefficient, or I'd see it on the scangage.
I'm not going to mess with those vortex generators. That might help for a box shaped truck trailer, but I don't think it will buy any measurable MPGs for a car thats already fairly efficient.
BTW, 53 mpg vs 40 mpg is a 32.5% increase.
Not trying to be a "naysayer", just haven't found any measurable improvement from areo changes, and I think some of you are dramatically overestimating potential percentage increases in fuel economy from the mods you are suggesting. Then again, if the percentages you are giving are for drag reduction, they might be correct, but its just that reduction in areo drag won't increase fuel economy by the same amount.
Someone posted a thread on this, but I never saw the article/URL until now.
That side view of the red camaro reminds me of CO ZX2's air dam.
From a practical urban driving standpoint, it would be cool if the air dam was retractrible below 40 MPH. It would probably need to be in 3 parts, 2 sides and a front, where the front overlaps onto the sides to make sure no frontal air gets into the seams on each side.
I like the way that the Mythbusters did their tests with the golf ball car myth. Even though they didn't use ABA, they did use a small removable fuel tank and weighed it before and after each run, simply because they didn't have the time to run a whole tank of gas with each mod. That is just something I might try in the future, making it possible to determine the improvement (or not) of something in just one afternoon.
Until this moment all that I have known
Is death's attempt at imitating life
And for the first time I am truly alive
-Becoming the Archetype