Tuesday, July 15, 2014

Fuel Efficiency, A Perspective...

#1 Blogdaughter sends in this interesting story about fuel efficient American cars and trucks... from the 1950s through the 1970s...

5 fuel-efficient American classics
Classic American cars, while full of style and presence, weren’t known for their ability to stretch miles out of a gallon of fuel. These are five of our favorite exceptions to the rule, all capable of at least 20 mpg:
The first of which is an extremely interesting model:

(picture from here)

1976 Plymouth Duster:
The Feather Duster was an interesting and little-known response to the 1970s fuel crisis. Unlike today’s diesel and hybrid options, it carried just a small premium over the normal Duster, a $50 “economy” option that substituted aluminum for steel in several areas that brought the weight down to about 2,700 lbs. The Feather Duster was capable of up to 36 mpg.
Now, I suspect that the Duster that got 36 MPG had the infamous "slant six" engine (the 198 CI model, not the 225 CI one, if I were a betting man). I'd also gather that the 36 MPG figure comes from an unrestricted (i.e. none of the modern emissions components that robbed cars of power in the late '70s through the early '90s) and represents highway driving of an extremely conservative nature. Very interesting that they were able to achieve that kind of mileage by a simple weight reduction, though.

Some of the other cars on the list aren't as surprising. The Crosley Hotshot, not exactly a household name, offered an astonishing 48 MPG in 1950. With a 44 CI motor, though, it's doubtful this car could hold its own on the highway - remember that my Harley has 88 CI, and while it's heavy for a motorcycle, it's still at least half  the weight of the Crosley, with double the engine... The Corvair isn't all that surprising, either - 24 MPG in the days before emissions restrictions really doesn't wow me, especially for a car that was considered compact for the time.

I had a 1983 Cadillac Coupe De Ville with the horrible 4.1L V8 engine. On the highway, it would get low 20s MPG without fail. It also had a 25 gallon tank, which meant it had between 500 and 600 mile range. We had friends with a cabin on a lake in upstate Maine, and one time we took the Caddy up there over July 4th with full camping gear, a long weekend's worth of clothes, food for everyone, and other assorted items in the trunk. With room to spare.

Oh, and there were four snow tires in the trunk as well - and it still got > 20 MPG...

What is surprising is the Cutlass with the 400 CI V8 that got 20 MPG. If I were a betting man, I'd wager that the 20 MPG figure was achieved at max efficiency: constant speed, no windows open, no external devices robbing power from the motor (AC/radio/etc.). The Earthf**ker gets 19 MPG on the highway under average conditions; I suspect that if I were to really streamline things I could see 20 MPG (or at least 19.5...).

One thing that hasn't changed is that making a vehicle lighter saves gas. I wonder what could be done with the materials we currently have available, from carbon fiber to titanium and other exotic metals. Oh, the car would cost a ridiculous amount of money (and, as such, would be subject to the same mathematical scrutiny as applied to high-priced hybrids and electric-only cars), but it would be an interesting exercise to see just how good a standard gas engine can be on gas...

That and it'd be neat as heck to have a car made out of the same material as the Snubbie from Hell™...

That is all.


Lupis42 said...

The Jag XJ is one good example - being all aluminum, it manages to break 20 mpg despite being a big luxury car that can hit 60 in under 6 seconds.

The Alfa 4C is another awesome one - under a ton thanks to space age materials, meaning 35 mpg and 4.5 seconds to 60.

Stretch said...

My '68 Cutlass had a 350cid and I was lucky to get 13 mpg.
Down hill.
With a tailwind.

Geodkyt said...

RE: 1976 Plymouth Duster fuel efficiency.

Look at the lines of the rear end -- WAY better at avoiding a nice vacuum dragging behind the car, compared to 1975 and earlier models. Still not a highly aerodynamic form, but at least it isn't trying to pimp-slap the atmosphere into submission.

I don't know what the MPG for the standard Duster with the 198 (which was a really common fit in those mid-size MOPARS; I think I've seen more 198s than 225s in those frames. . . I, of course, had a iron blocked 318 V-8 in my '75 Dart Special Edition; the mileage was "Hit the accelerator and watch the fuel needle drop" ;-) )