Massive air dam on '98 Geo Metro (Firefly), A-B-A coastdown test; Update: version 2

[Frank Lee]

I'd ask Pa what he got with the Vega but he never figures mpg and his foot's pretty heavy. Heh heh, he let me drive that thing when I was 11... fun!!!

[JoeBob]

One thing I will say about that car was that it was a trooper. My friend changed its oil once, at about 30k, because he felt guilty about letting it go. He dang near totaled the car shortly after getting it (new), it was repaired, and had very little maintenance. After owning it for about five years, he sold it to another friend of mine who was one of those people who could just walk near a car and kill it. He had a '49 Ford and a '65 Merc. Comet which both lasted him just a few weeks before they just up and died. I guess it ran in the family...his father apparently had owned a fleet's worth of '56 DeSotos, he'd drive one 'till it died (took maybe a few months), then he'd get another. Anyway, this Pinto lasted my second friend over a year before it gave up the ghost. I remember borrowing it after he owned it, and having to add three quarts of oil...it was off the stick. Fords are pretty tough cars (can't explain the early demise of the '49 and '65, tho).

[gasstingy]

I bought my first new car a few months after I graduated from high school, a yellow and black 1976 Pinto (Pony MPG) Stallion Hatchback. 2.3 liter, 4-speed manual, AM radio and Air Conditioning. The Stallion Package came with a blacked out hood (except for the front ~2"), lower sides blacked and the blacked out part went over the wheel openings (about 2 or 3 inches) too. The tail light panel was blacked out as well. It came with styled steel wheels and white letter radial tires. I loved this car. I joined the Air Force and would drive home every chance I got (325 miles one way) to visit my girl friend, until we got married. Speed limit was 55 mph on the interstate, so I put in a CB radio and drove mostly 60 when someone screamed cop and 85 when they did not. I got several speeding tickets. I also got 28 mpg most of the time. My mom later bought a new 1980 Pinto, 2.3, automatic and air conditioning. Her and my dad drove to Utah to visit us (from Alabama) and averaged 25 mpg.

The Pinto was probably my favorite car ever, mostly for all the memories I made during the time I drove it:-)

[Sulfuric]

That pinto may have been in bad shape, I get ~37mpg @ 70mph in my corolla. I know they are very different cars but both are 4 bangers and I doubt I should be getting more than 2x what the pinto got.

[rdtony]

Air dams work on race cars; make sense for street cars!

[JackMcCornack]

Air dams are pretty much a sure thing for reduced lift, which is the primary goal for race car aero, but for a car with a smooth belly, they may not reduce drag. They usually reduce Cd, but that's at least partly because they increase frontal area. I think.

[Galane]

1971 through 1974 Pinto has breaker points ignition. Maintaining that plus keeping a carb in tune, along with maintaining the spark plug gap over time was required to get and keep optimal MPG.

Starting in 1974 the Pinto shared its front suspension (and damn little else!) with the Mustang II. 1975 brought electronic ignition across the board at Ford, removing one of the most finicky fiddly maintenance jobs on a car.

The 2.3L engine was new for 1974. 1971-1973 the Pinto had either the little 1.6L "Kent" or the 2.0L. One rather "WTH?" "feature" of those engines was the cam bearing journals were all different sizes, smaller towards the front. No removing the cam with the head on the engine, in the car, as is possible with the 2.3L.

IIRC it may have been possible to order the 2.0L in a Pinto from 1974 to ???? Why anyone would *want* to have a 2.0L in one...

Racer Walsh was to Pinto as ANDIAL was to Porsche in the 1970's. The RW catalog was chock full of go-not-as-slow goodies.

What would be interesting to test is a MegaSquirt on an old 1975-1981 Pinto to see how much MPG can be squeezed out, otherwise stock and with some aero mods.

Then there was the 155+ MPH 1980 Mercury Capri (with the "I'm a Porsche 924 wannabe!" bubble hatch and rear bumper*) with one year only 255ci V8 and some lightening, aero and gearing mods. Took a bit to get up there but once up to speed...

*I'm serious. Compare the side views of the two, the rear slope/curves are practically identical. Too bad FoMoCo never made the better looking twin in a notchback coupe.

[olmon]

On the Pinto economy, C&D must have really beat on the car they had to use that much gas. I owned a 74 Pinto StaWag with 2.0 & C4 auto back in the late 70s/early 80s. I never got less then 20 MPG & typically got in the 25-6 range & I didn't baby it at all. At the time, I was commuting approx. 30 miles one-way with numerous stops & turns.

[MetroMPG]

I haven't had an air dam on the Firefly/Metro since I posted this thread back in 2009. However, inspired by Tim's recent Metro lawn edging air dam thread, I just did something similar.

I've done a couple of air dams since 2009, just not to the Firefly, eg:

• I added & tested one (as part of a set of mods) on my "winter beater" 2007 Honda Civic (since sold)
  
  
• I did the same thing on a 2014 Mitsubishi Mirage loaner
  
  
• I also stuck one on the 2015 Nissan Micra loaner I had recently
  
  

Here's the Firefly's version 2.0 ...








Tim used metal brackets to mount his in a very respectable one hour of tinkering time. Very quick 'n' easy, but it can have an uneven, "wavy" look to the edging, so I took a slightly different approach.

1) I trimmed a length of 1x3 wood to match the curvature (plan) of the bottom of the bumper (front face) where the lawn edging would attach. Then I attached the wood to the bumper and screwed the edging into the wood.

2) To take the waves out of the bottom of the edging, I screwed 2 layers of coroplast to the back side to make it thicker.

3) To stiffen the air dam to keep it from being pushed backward, I screwed a couple of scraps of edging between the air dam and the wood, under tension:



Each one is just touching a screw that comes through the air dam, so they're pretty stiff/secure. But not so secure that they won't give way if (when) I hit the air dam on something.



It's got 5 inches ~13 cm of clearance. A bit more than I would like, but one of these years I'll lower the car an inch or 2 and make it just right.

To finish up, I just need to dab some black paint on the screw heads to hide them a bit.

[Daox]

Interesting mounting, looks good though!