27 MPG with a 1985 4.1 V8 Cadillac

[Joe771476]

And carmakers today are bragging about 35 MPG?! Don't laugh about the Caddy! I inherited it; I never would have paid for one! But this is an underpowered V8! Yes, I don't run up to red traffic lights and I don't floor it to reach the speed limit within 1/10 of a mile. But these cars are 22 and 12 years old! And today we can only get 35 MPG? Even most hybrids don't get the 52 MPG I used to get with a 96 Sentra! Something is wrong!

[lfeg]

Hey Joe, the key is your statement "But this is an underpowered V8!". Horsepower uses fuel. More hp uses more fuel. Another issue is weight. the more weight you are moving, the more fuel you use. I bet that old Caddy is below 4k pounds. Anyone rember the old Geo Metros? That car with the 3 cylinder engine and a stick would get fantastic mileage, even when you were flogging it to keep up with freeway traffic. 50 mpg was not out of the question. But then again that was a car without air, power windows power seats, and all the other weight adding, power sapping stuff we demand today.

[JLaudioF150]

Good post and good point. My brothers 2002 WS-6 Trans Am would see 27 mpg and I wouldn't exactly call that v8 underpowered. It was a stick though.

 

I used to see 30mpg in my 1993 cougar v6. But, that was waaay underpowered for a heavy car.

[Devodev]

Good post and good point. My brothers 2002 WS-6 Trans Am would see 27 mpg and I wouldn't exactly call that v8 underpowered. It was a stick though.

 

I used to see 30mpg in my 1993 cougar v6. But, that was waaay underpowered for a heavy car.

 

That was the first thing I thought about reading the post. My friend had a '99 Camaro SS that would get in the upper 20's mpg. Then he could go to the drag strip and pull 13.0's. Not a bad combination and not that old of a car. He would debate with another guy at work about his Prius to show that he didn't have to sacrifice a fun car for a "boring" fuel efficient one and these cars could be built. Just the SS certainly wasn't advertised for its fuel efficiency.

 

Someone once said that many GM cars seemed to get pretty good gas mileage compared to others in its class and I think the Vette isn't quite that bad.

[atomaro]

Some pretty bold statements about fuel economy. Either these guys stole some sails from the Black Pearl or we seriously need to rethink the way we teach Math in this country.

[Ford Jellymoulds]

Maybe Ford should bring back the 1908 25 MPG Model-T and do a hybrid version?

 

Motor trend says....

I heard this again on the news the other day: The original Model T Ford, launched 100 years ago, got 25 mpg. Since then we've split the atom, put a man on the moon, and invented spray-on cheese. All these technological advances, and yet the average gas mileage of our car fleet today is barely 21 mpg. Clearly the auto industry is ripping us off, most likely in cahoots with Big Oil.

http://blogs.motortrend.com/6237208/editor...tter/index.html

[Harley Lover]

It might be noteworthy to compare how much pollution the 1985 Caddy is producing from its V8 versus a 2008 V8. The current model V8 probably produces a small fraction of the pollution that the 1985 model produced, yet still produces amazing power and economy. And, as others have noted, if the current V8 were detuned to the power levels of the 1985 engine, I 'think' it would produce superior mileage numbers.

[old_fairmont_wagon]

And my dad's old 1980 Mercury Grand Marquis with a 302 V8 under the hood, and without the "innovative" variable venturi carburator could manage 30 mpg on the highway between New Orleans and College Station, TX. If there ever was a land yacht, that was surely it. It wasn't underpowered, it still had a portion of the emissions controls for the period, and it wasn't a particularly light vehicle.

 

That being said, lets take a quick look at what's changed over the years...

 

Crash survivability standards have risen a great deal over what they were 25 years ago. To meet just the standards for crush resistance and energy disipation, vehicles have had to use more structural reinforcement, stronger (and heavier) alloys of steel are being used, and greater amounts of interior padding have been added. All of this has increased the amount that vehicles weigh.

 

Safety gear mandated by the gov't has also increased. Airbag units are not without their weight penalty. Antilock brake system control units add a little weight. It all adds up.

 

Comfort and convenience gear is more and more present on vehicles today. Electric window motors weigh more than the manual crank systems did. Power lock systems add weight. Almost every vehicle produced has A/C in the US now. Entertainment systems add a bit of weight. NVH reduction measures like noise insulation, complex engine mounts, structural isolation units, etc add weight.

 

Engine power output has risen over the years. My 85 LTD had miserable power production from its 3.8L v6. My 92 Tempo didn't even have 100 hp from a 2.4L engine. The 06 corolla I had produced 125 hp from a 1.8L engine, weighted about as much as the tempo did, and still got 10 mpg better on the highway than the tempo ever managed.

 

Everyone loves to wax poetic about the Metro, or those old Sentras, but they don't remember seeing the shredded remains of those vehicles after accidents that would have been survivable today. Even the freaking Smart four2 is safer then those tin cans were. They may have gotten great gas mileage, but you sacrificed safety to do so.

 

People love to bag on the fact that gas mileage hasn't risen much, but they forget that most v6 fmid-sized amily sedans on the market today produce quarter mile numbers that were considered good for vehicles that were considered production sports cars in the 90s. Most 4 cylinder mid-sized sedans on the market today have similar performance to production sports cars in the 80s. These are not stripped down vehicles either (like many of those sports cars were), they have many power options, A/C, cruise control and decent entertainment systems. They can comfortably carry 4 or 5 people long distances reliably all the while producing markedly less toxic and/or polluting emissions.

 

So, yes, I'll take a modern vehicle over one of those old ones any day of the week, and I won't complain that the auto makers haven't released the magical 100 mpg carburator yet.

[NickF1011]

It might be noteworthy to compare how much pollution the 1985 Caddy is producing from its V8 versus a 2008 V8. The current model V8 probably produces a small fraction of the pollution that the 1985 model produced, yet still produces amazing power and economy. And, as others have noted, if the current V8 were detuned to the power levels of the 1985 engine, I 'think' it would produce superior mileage numbers.

 

Might also be noteworthy to see how well a 1985 Cadillac would take a front or side impact from another vehicle. All that safety cage and airbag stuff isn't light for sure.

[Harley Lover]

Might also be noteworthy to see how well a 1985 Cadillac would take a front or side impact from another vehicle. All that safety cage and airbag stuff isn't light for sure.

Yep.

[jasonj80]

Never mind that one of those cars pollutes more in 1,000 miles than a modern engine will pollute in 100,000miles

[lfeg]

Maybe Ford should bring back the 1908 25 MPG Model-T and do a hybrid version?

 

Motor trend says....

I heard this again on the news the other day: The original Model T Ford, launched 100 years ago, got 25 mpg. Since then we've split the atom, put a man on the moon, and invented spray-on cheese. All these technological advances, and yet the average gas mileage of our car fleet today is barely 21 mpg. Clearly the auto industry is ripping us off, most likely in cahoots with Big Oil.

http://blogs.motortrend.com/6237208/editor...tter/index.html

 

Red herring. The Model T could get 25 mpg when driven steadily on smooth roads at about 25 to 30 mph. Try driving one as you would drive a modern car (either stop and go city, or 50 + mph (50 is possible) highway and you would see the mileage go down drastically. You must remember that the T had about 20 hp, and a very low weight.

[NickF1011]

Red herring. The Model T could get 25 mpg when driven steadily on smooth roads at about 25 to 30 mph. Try driving one as you would drive a modern car (either stop and go city, or 50 + mph (50 is possible) highway and you would see the mileage go down drastically. You must remember that the T had about 20 hp, and a very low weight.

 

Not to mention the Model T doesn't even use the same fuel as a modern car.

[therealmrmustang]

Some pretty bold statements about fuel economy. Either these guys stole some sails from the Black Pearl or we seriously need to rethink the way we teach Math in this country.

 

 

Bold?! I don't think so...

 

I used to own an '86 Mercury Capri 5.0 and it would regularly get 28 freeway and 22 combined. On a trip home from Sacramento I got almost 30 (...29.6).

 

I think the issue with fuel economy now is weight and the quest for more power. Cars weigh a lot more than they used to because of all of the mandatory saftey equipment and reinforcements. Then to move these heavier cars you need more power, and there has been a horsepower race for the last 20 years. Those factors alone burn more fuel.

 

Go and get yourself any publication from the late seventies to the mid eighties and look and the advertised MPG ratings. Toyotas, Hondas, and some Fords for that matter were getting better that 40 mpg. But a Toyota Corolla of that vintage might weigh 1900 to 2100 pounds... wet!! A friend of mine routinely buys early nineties Civics as commuter cars because they consistantly return 42 to 46 mpg... sometimes better.

[Ford Jellymoulds]

Not to mention the Model T doesn't even use the same fuel as a modern car.

 

Who would have thought back in 1908 that the Model T would still be beating the CAFE 20.8 mpg average 100 years later, real cutting edge stuff 25 MPG in the US you have got to agree, maybe Ford should rebuild a few again to up it's CAFE limits.

http://www.wanttoknow.info/050711carmileageaveragempg

Edited April 16, 2008 by Ford Jellymoulds

[V8 Ford]

Maybe Ford should bring back the 1908 25 MPG Model-T and do a hybrid version?

 

Motor trend says....

I heard this again on the news the other day: The original Model T Ford, launched 100 years ago, got 25 mpg. Since then we've split the atom, put a man on the moon, and invented spray-on cheese. All these technological advances, and yet the average gas mileage of our car fleet today is barely 21 mpg. Clearly the auto industry is ripping us off, most likely in cahoots with Big Oil.

http://blogs.motortrend.com/6237208/editor...tter/index.html

Engineering of cars since the Model T has focused on increasing performance, refinement, comfort, safety and cleaning up emisions to reduce impact on air quality. Demand for operating costs of the car (ie: fuel economy) hasn't changed very much, hence optimization of the former characteristics was performed with respect to constant operating costs. More emphasis on efficiency has been placed on cars now (for obvious reason of increased fuel prices, sustainability and environmental concerns of global warming), but the result is worse characteristics at the same price. Compare a Toyota Prius with any other car at the same price and the prius might beat it on efficiency, but for every other desirable characteristic in a car it will come up short. Blaming the oil companies and ignoring economics works great for political reasons though.

[Ford Jellymoulds]

Engineering of cars since the Model T has focused on increasing performance, refinement, comfort, safety and cleaning up emisions to reduce impact on air quality. Demand for operating costs of the car (ie: fuel economy) hasn't changed very much, hence optimization of the former characteristics was performed with respect to constant operating costs. More emphasis on efficiency has been placed on cars now (for obvious reason of increased fuel prices, sustainability and environmental concerns of global warming), but the result is worse characteristics at the same price. Compare a Toyota Prius with any other car at the same price and the prius might beat it on efficiency, but for every other desirable characteristic in a car it will come up short. Blaming the oil companies and ignoring economics works great for political reasons though.

 

There are lots of cars some that are half the price of the Prius to buy new that get better MPG like a Pug 207, even a Ford Focus 78 UK MPG econetic diesel get more MPG than a 67 UK MPG Prius without $3,000 batteries that will have replaced when they no longer hold there charge.

http://www.whatcar.co.uk/car-comparison.as...9&ED3=52893

Edited April 16, 2008 by Ford Jellymoulds

[atomaro]

Bold?! I don't think so...

 

I used to own an '86 Mercury Capri 5.0 and it would regularly get 28 freeway and 22 combined. On a trip home from Sacramento I got almost 30 (...29.6).

 

I think the issue with fuel economy now is weight and the quest for more power. Cars weigh a lot more than they used to because of all of the mandatory saftey equipment and reinforcements. Then to move these heavier cars you need more power, and there has been a horsepower race for the last 20 years. Those factors alone burn more fuel.

 

Go and get yourself any publication from the late seventies to the mid eighties and look and the advertised MPG ratings. Toyotas, Hondas, and some Fords for that matter were getting better that 40 mpg. But a Toyota Corolla of that vintage might weigh 1900 to 2100 pounds... wet!! A friend of mine routinely buys early nineties Civics as commuter cars because they consistantly return 42 to 46 mpg... sometimes better.

 

 

I'm still standing behind my exaggeration theory.

[grbeck]

And carmakers today are bragging about 35 MPG?! Don't laugh about the Caddy! I inherited it; I never would have paid for one! But this is an underpowered V8! Yes, I don't run up to red traffic lights and I don't floor it to reach the speed limit within 1/10 of a mile. But these cars are 22 and 12 years old! And today we can only get 35 MPG? Even most hybrids don't get the 52 MPG I used to get with a 96 Sentra! Something is wrong!

 

Cadillacs from that time were hardly powerhouses, and they had a fairly flimsy (but lightweight) structure, even by the standards of the day.

 

To drive one is to understand why upscale customers were flocking to Mercedes-Benzes, BMWs and even Town Cars in those days.

Edited April 16, 2008 by grbeck

[dave91gt]

I too agree with some of these statements. I have a 91 Mustang GT with a T5. That car(for it's day) was fairly sophisticated and safe (airbags). With a stock motor and bolt on's (3.55's, exhaust, cai) it would pull mid twenties on the interstate and run 7.80's on the dragstrip with a 100 shot (while weighing 3200 or so lbs.). Granted my new motor will not pull that. I had an 03 GT 5 speed all stock and managed 28 mpg. going to the OBX. Then there was the 88 Escort EXP that pulled high 30's on a trip. Underpowered, yes, but it had a sunroof and AC. The fact is, manufacturers are feeding our desire for performance and safety and the fuel mileage has been the thing to suffer as well as complicating cars and trucks. Just look at the diesel 3/4 ton's. Their fuel mileage is horrible compared to say an early nineties Cummins or Powerstroke. A 4.10 geared RC Cummins could easily knock down low 20's from talking with people I know, yet the new trucks dream of it. However, the new trucks are quiet and powerful. Another experience- my wife bought a new 2001 Dodge 1500 QC with a 318, auto and 3.55's (4X4). That pig never got over 12 mpg with the average being in the elevens. To top it off, it had zero power. I at the time had a 78 F150 with a built 400M, 4 speed, and 4.10's that would jerk the tongue off of a trailer and get 10 mpg empty while doing it. However, the F150 had crank windows and no AC.

[therealmrmustang]

I'm still standing behind my exaggeration theory.

 

There's no exaggeration to plain ol' grammer school math... #gallons / distance travelled = miles per gallon. My Capri had the stock 225/60-15 tires, so the mileage was reasonably accurate.

 

You can stand behind you theory... but facts are facts.

[theVengineguy]

Never mind that one of those cars pollutes more in 1,000 miles than a modern engine will pollute in 100,000miles

 

Thankyou for contributing at least one word of wisdom. I mean c'mon, comparing the standards that built a 1985 Caddy to 23 years later is crazy. Comparing a 1996 Nissan which would probably be gauranteed to kill you in an accident to a 2008 Focus with 6 air bags, it's like apples and oranges. Complain about 35mpg, thats pretty damn good considering the revised EPA drive cycle.

 

I would believe your Caddy gets good fuel economy, every day it gets lighter as it rusts, same said if you still had the Nissan.

[IMSA-XJR9]

I used to own an '86 Mercury Capri 5.0 and it would regularly get 28 freeway and 22 combined. On a trip home from Sacramento I got almost 30 (...29.6).

 

I used to own it as well! :shades:

 

I just took a 600 trip in my vulcan 3.0 Taurus and averaged 31mpg @ ~70mph over many elevation changes. Heck, for the first tank I averaged 34 mpg @ 70mph. It should be noted that was on 93 octane as I have switched over to 91-93 octane on my last two daily driver cars as they approached 100K miles. I sold the Explorer at 215K miles still running strong and switched my current Taurus over to 91-93 at about 85K (have 118K now).

Edited April 17, 2008 by IMSA-XJR9

[atomaro]

There's no exaggeration to plain ol' grammer school math... #gallons / distance travelled = miles per gallon. My Capri had the stock 225/60-15 tires, so the mileage was reasonably accurate.

 

You can stand behind you theory... but facts are facts.

 

 

And the "facts" are easily exaggerated on the Internet. 20mpg easily becomes 28mpg to continue the conversation. I can understand the tempo from the previous post, but the 5.0 capri and LS cars mentioned earlier. Just from the fact that it is very hard to keep your right foot out of it for over 300 miles. Everyone has a car or had a car that easily whoops epa and manufacturer estimates. Individual examples don't mean a lot to me...sorry for not agreeing.