Why did cars of yesteryear have poor mileage?

[raccoon]

I know that when gas was cheap, nobody cared about poor gas mileage.

I'm just wondering why the cars had poor mileage, especially with no AC.

[Hoyt]

1. Bigger engines, old technology, heavier, stupid drivers (including me), transmission gearing, etc.

But, the relatively cheap price, little competition based upon gas mileage, lack of government interest in enforcing higher gas mileage, lack of public interest/recognition, etc., was probably the main culprit. Back then, everyone smoked and ate trans fat too.

Oh, in the 1960s and early 1970s there was a rumor that some guy developed a carburetor that got 200 miles to the gallon, but the auto companies bought the patent and hid it. Didn't believe that one, but the conspiracy theorists did.

[Packerowner740]

27. That guy in the 70s was Tom Ogle and his design did away with the carb

I've done quite a bit of research on this as his daughter Sheri is a friend of mine. We were just talking about it this past weekend. He claimed his car ran off gas fumes, therefore removing the need for a carb and drove his car from El Paso tx to deming NM and back on 2 gallons of gas.

According to Sheri and newspaper accounts, he was offered 25 mil for his invention but refused it, thinking he was going to be richer than he could believe. He went from having no money to having investors, wearing expensive watches, heavy gambling, buying large quantities in stocks like IBM.

Her dad died when she was just five under mysterious circumstances and his ideas went with him.

[Dont call me Shirley]

30. 104.6 miles one way

[Hoyt]

33. And in all these years, no one has come up with a similar device. It''s BS.

Someone would have broken from the pack and made a car with the device/mechanism.

[RKP5637]

31. There was another one back then I heard about wheel bearings ... some guy in Chicago I believe

had invented frictionless wheel bearings and tires with minimal drag that allowed a car to coast for miles. ... and the auto companies bought him out! Sounded like BS back then to me, same today!

[Turbineguy]

2. Cooler engines, lousy gas miliage.

a big loss was cooling. Thermostat setting used to be 150 Deg F, now 210.

Less cooling heatloss, less gas needed, less exhaust, less gas needed. Lower friction, less loss.

It all works together.

The radiator on my newer 250HP car is smaller than my 60HP car of the 1960's.

Also now, better combustion control, VIT VVT it goes on.

[Populist_Prole]

3. Several factors

Last edited Sun May 24, 2015, 06:37 PM - Edit history (2)

Less precise control of the fuel/air ratio due to Pre-EFI setups. Carburetors needed to be adjusted and maintained to provide optimal driveability and efficiency. Many were neglected.

Pre-electronic ignition era engines didn't stay in optimal tune very long because there was wear on the various moving parts of a point/condenser ignition.

Other than single purpose high-performance use, many engines were "de-tuned" or under stressed for longevity/reliability, but this decreased efficiency, volumetric and otherwise.

Another important factor was that overdrive transmissions were seldom used except in a few specialty applications....and in trucks, which is outside the purpose of this discussion. This meant that with top "high" gear being 1:1, the only way to control the final drive ratio was through the rear axle/transaxle ratio. It had to be low or "short" ( numerically high ) enough to provide adequate enough initial acceleration, especially on weaker engines with little low-end torque. This made cruising RPMs too high, especially if the rear axle was geared toward high acceleration. If cruising RPM was to be kept low, initial acceleration would be too lethargic. Larger displacement engines were more tolerant of "tall" axle ratios but then you're talking big engine and big car...which works against fuel efficiency.

Concurrent with all these developments, you had much improved quality metallurgy and lubricants, which allowed tighter clearances and for the engine to be stressed and in a higher state of tune and thus more efficient.

Then we throw in wild cards like shapes and length of the intake/exhaust paths and stuff like combustion chamber design.

An interesting evolvement. A 1960's VW bug was, comparatively, a gas sipper in its day, but the engine was detuned and the gearing less than optimal. 25 mpg was a common figure. A fire breathing V8 mustang of today gets better mileage than that even in daily life....provided you're not barking the tires through every gear at WOT.

[Major Nikon]

5. The first one is the biggest factor

Most piston aircraft have very old engine designs which haven't changed much in the past 60-70 yrs or so. Most of them have manual pilot controlled fuel/air mixture controls. So long as the pilot knows what they are doing, the mixture can be adjusted to rival the efficiency of the most advanced auto engines of today.

[Enthusiast]

10. What an excellent post!

I find the combustion chamber/cylinder head design to be a fascinating factor.

[Spitfire of ATJ]

15. I still have one of these...

[MADem]

4. I have a subcompact from the mid eighties that SIPS gas.

It's no hybrid, but it gets thirty and sometimes more in good conditions (like a tail wind ).

It has a/c, too--but I lose a little MPG using that.

[ret5hd]

6. What's the top end with a head wind? 30 mph?

just kidding!

[MADem]

11. It goes faster with fewer passengers--and if I've got the back seat down and it's stuffed with crap,

that might slow me down a hair, too. It's a five speed standard, though, and it still has decent pick-up. It'll never be mistaken for a Porsche, but that's fine w/me!!

[Art_from_Ark]

20. I had a late-'80s compact that got 50mpg on the highway.

5-speed manual transmission.
I didn't do a lot of city driving.
Maximum speed was about 70mph.

[MADem]

21. I can get mine up to 90 and then some with a tail wind!

I know because I got popped by a cop for speeding--I was only able to beat the rap because the cop made a mistake filling out the ticket!!! PHEW! The guy was a real jerk about it, too. I just kept my mouth shut and my hands on the wheel, As You Do!

I am not normally that much of a leadfoot--it was a great sunny day, I wasn't carrying anyone or anything in the back, and it was a long down hill!!!

[aint_no_life_nowhere]

7. One of my old cars gets nearly 40 mpg

It's a '61 Renault, one of the lightest production cars ever built at about 1200 lbs (about 400 lbs. lighter than a VW bug. All my old cars get good gas mileage even though they have carbureted engines which is less efficient than fuel injection, because they are small and light ('61 Renault, '69 Citroen DS, '73 Saab 96, '57 DKW 3=6). They all have small engines with small displacement with only 4 cylinders except the DKW which is a 3 banger. In my opinion they are much prettier to look at than the horribly ugly and grotesque cars made today and they are more fun to drive. Today's car in my opinion has no spirit, no style and usually is very heavy, like a tank. I will never own a new car.

[Enthusiast]

9. Wow! You sure have some interesting old cars!

You must be mechanically inclined.

[hunter]

22. Yep, I've had old cars that got great mileage.

And they really were not all that dangerous compared to other cars of the day.

My grandma's big gas hog Cadilac scared the shit out of me a couple of times while I was driving it and the unexpected happened. It was a massive vehicle, fast too, but it handled like a boat. Fast reflexes wouldn't save you like they might in a lighter more nimble car. The ten foot log that fell off a truck and was bouncing down Highway 101, sort of end to end, that I deftly dodged in my little Toyota might have killed me in the Cadillac. I wouldn't have been able to dodge it.

My brother inherited grandma's Cadillac and had it parked on the street in front of his house. A drunk driver, who couldn't have been driving all that fast on a residential street, rear ended it and destroyed it. Being a drunk driver in a more modern car, he walked away relatively unscathed, and of course he was uninsured. But I'm not so sure anyone in the Cadillac would have escaped serious injury in that sort of collision.

[progressoid]

24. 1959 Chevrolet Bel Air VS. 2009 Chevrolet Malibu

[hunter]

25. Yeah, like that.

[Enthusiast]

8. Great posts.

There are many factors.

One factor is the old style torque converter in automatic transmissions. In modern times torque converters "lock" so the mileage figures are now similar for cars equipped with manual and automatic transmissions. There used to be a significant loss of MPG with automatics due to slip in torque converters.

Additionally all vehicles now have "overdrive" transmissions. It used to be automatic transmissions had only three and sometimes only two forward gears. This forced the engines operate in a less than ideal rpm range. Now automatic transmissions seldom have less than five speeds allowing the engines to operate at a relaxed pace that requires less fuel.

Toward the 2,000s there was a real effort to decrease wind drag on auto bodies. This mostly increased the highway fuel economy.

As several have mentioned, electronic fuel injection has been adopted on virtually every passenger car engine. Not only that but the engines are equipped with sophisticated "engine management systems". The computer uses sensors that determine the optimal air fuel mixture and automatically adjust the fuel injection and ignition accordingly. Due to emission requirements a vehicle must remain "in tune" for 100,000 miles. This means your car is no longer subject to huge variations due to wear on ignition components as in the past.

Remember when you had to replace your "points, plugs and condenser" every 20,000 miles or so? Now your car has 100,000 mile rare earth iridium spark plugs and there are no points or condenser.

All these things work together to increase your MPG.

[seveneyes]

12. Physics, more weight, heat loss, the curve of learning

[malthaussen]

13. The old Metropolitan, built in the 1950s, got 50 mpg...

... under some rather stringent test conditions, but still...

-- Mal

[Spitfire of ATJ]

14. Part of it was the steel....

The production went from iron ore to finished car.

The more times you melt down steel, the lower the impurities and the stronger it gets. Those older cars not only had to be thicker steel for strength but they rusted out faster.

[Tobin S.]

16. K&R. Some good info in this thread.

[RebelOne]

17. I had a little Ford Cortina in the late '60s

That car would go forever on a full tank. The bad things about it were that it had no power and whenever it rained or I went through a puddle, it would stall out.

[A HERETIC I AM]

18. What?....ya think this spectacular beauty should get more than 12?

LOL.....

You have gotten your answer, But I'll reiterate or add to the points about fuel delivery/combustion. Modern electronic fuel injection systems and their fuel management software are worlds removed from the system installed on the car above. Having said that, even with it's massive size and weight, that '53 Eldorado could probably reach better than 25 mpg with a brand new powerplant installed.

[olddots]

19. scary fact

Transmition fluid used to contain whale oil till around 1978 ......

[canoeist52]

23. 1981 Toyota Starlet 38/52. Why can't we make this now?

The first year for the Starlet in the United States was 1981, when Road & Track called it the “commuter car for the 1980s.” During its brief stay in the United States, the rear-wheel-drive, 1.3-liter-engine Starlet liftback was billed as “cheap to keep” with stunning gas mileage (38/52) and strong reliability

http://www.toyoland.com/cars/starlet.html

[KeepItReal]

26. Honda Civic HF 40 MPG City / 47 MPG Highway on regular gas

http://www.fueleconomy.gov/mpg/MPG.do?action=mpgData&vehicleID=7474%20%20&browser=true&details=on

[bobjacksonk2832]

28. Cars back then weighed like 5000 tons or something

Not to mention, they had a lot more horsepower than the average family sedan.

[struggle4progress]

29. I know! I know!

Cuz the miles were longer and the gallons were smaller, back in the day

[olddots]

32. I had 63 V.W. Micro Bus that got great milage

most of the time we pushed it or towed it to gigs .