Massive air dam on '98 Geo Metro (Firefly), A-B-A coastdown test; Update: version 2 - Page 3 - Fuel Economy, Hypermiling, EcoModding News and Forum

cfg83 · 08-20-2009, 12:09 AM

Frank -

Quote:

Originally Posted by Frank Lee

I still can't get over a 4-banger Pinto only getting 14.5mpg.

My 4x4 V8 F150 does better than that unless I'm towing. Used to have an F250 4x4 with a 460 V8 that got 13-14 NO MATTER WHAT. There is something wrong with this equation.

I don't remember them being THAT bad, 70 mph notwithstanding.

I got around 20ish with my 283 V8 a/t equipped Nova- supposed to be 55mph but often was closer to 70.

Was their car messed up?

I don't know. I wanted to "project" the Pinto's MPG at lower speeds, so I did this :

This is incorrect because I didn't give the Pinto an upward curve as the MPH lowered, I just kept it a straight line, parallel to the BMW 535i. However, I wanted to project on the side of lower MPG.

CarloSW2

Christ · 08-20-2009, 12:12 AM

My dad had a Pinto "fast back". I'm not going to be 100% accurate on this, but I do specifically remember him getting at least 25MPG with it, and it had a two point something engine. I don't believe it was a 2.3, but it was definitely stock, with a 4 or 5 speed transmission - don't remember which.

I'm only sure about the MPG figure being at least 25MPG because my Father wouldn't have been driving it if it weren't. He'd have sold it, as it wasn't our only car at the time.

Frank Lee · 08-20-2009, 01:01 AM

FWIW:

For '73-'74 Pintos:

Quote:

With its advertised 20-25 mpg, this was far ahead of the big Galaxies and LTDs that were lucky to see 12 miles from the same amount of fuel.

http://auto.howstuffworks.com/1971-1980-ford-pinto5.htm

Here's an "MPG" version for '75:

Quote:

Equipped with the four-cylinder engine, manual transmission, the new catalytic converter emissions device (which allowed engines to be retuned for better efficiency), and a 3.18:1 axle ratio in place of the 3.40 gears standard in other Pintos, the MPG had a government rating of 34 mpg on the highway, 23 mpg in the city. (Swapping the four-speed stick for an automatic earned a 30/21 highway/city rating.)

HowStuffWorks "1975 Ford Pinto"

All of that is quite a long way from 14.5.

cfg83 · 08-20-2009, 01:41 AM

Frank -

Would the 23/34 EPA rating for the Pinto be the "old school EPA" that was recently changed, or a different "old old school" City/Highway drive cycle?

CarloSW2

Frank Lee · 08-20-2009, 01:48 AM

Who knows?

I've been trying to track down something trustworthy re: Pinto fe but as of now what I put up is what I got.

I haven't even found the original C&D article. I want to see that, not filtered by all the recent coverage of it. I did see someone's comment that the car in question had the 2.0 with a/t.

Almost regardless of what I or anyone finds, I simply don't remember little '70's cars, rotten old-school automatic transmissions or not, getting fe THAT terrible.

cfg83 · 08-20-2009, 02:08 AM

Frank -

I just bought the March 1974 issue on ebay for $5 total. If the (Big Oil) rats haven't eaten the pages in question, maybe we can (literally) get to the original article.

CarloSW2

Frank Lee · 08-20-2009, 02:23 AM

Darin's got it too, but I haven't found anything online I can read.

MetroMPG · 08-20-2009, 10:24 AM

The C&D Pinto article is currently readable in scanned images in this eBay auction:

1974 FORD PINTO "Crisis-Fighter" ORIGINAL 1974 ARTICLE:eBay Motors (item 350168538404 end time Sep-17-09 07:59:49 PDT)

As for the poor initial MPG figures, I was just repeating what Car and Driver noted. FYI they used the 2.0L engine with the automatic transmission. At 70 mph, I don't have trouble believing the slushbox - probably a 3 speed? - would get pretty dismal mileage.

----

The air dam's A-B-A coastdown data is (are) crunched, and it appears to have helped. I'll post the gory details shortly.

MetroMPG · 08-20-2009, 01:23 PM

Here are the numbers:

For comparison: remember I did a test to determine the "resolution" of coastdown testing at the same speeds, trying to see if it could register the difference between the driver's window open vs. all windows up:

So, in conclusion: a giant ugly air dam apparently has a greater positive effect on drag than rolling up the the driver's window.

MetroMPG · 08-20-2009, 01:26 PM

Quote:

Originally Posted by Christ

Ricer. :P

HA!

The first comment I got - from a neighbour - was: "Now you're doing NASCAR?"

This is undoubtedly (not surprisingly) one of the most attention getting cardboard mods I've slapped on. Most rubber necking came from the fart can muffler crowd. I even saw one guy in a slammed loud Jetta stop in the middle of the road to look at it (take a picture?) when it was parked.