I am interested in what progress has been made with (internal combustion engine efficiency) in the last 40 years. (fuel, best)

[StealthRabbit]

Hyundi get amazing performance and economy from 1.6TD taxis (throughout Asia)

[victimofGM]

Just checked the UK Hyundai site. A Hyundai i30 comes with a 1.0L turbo with 118 hp while the same car in USA is 2.0L 148 hp in Elantra sedan). For direct comparison the USA Elantra GT comes with a 2.0L 161 HP base engine.

That 1.0L turbo fuel economy in US MPG is 47. The most efficient USA Elantra is 40 mpg with a 1.4L turbo with 128 HP and 40 MPG HWY & 32 MPG city.

[corolla5speed]

Originally Posted by victimofGM

OP, look up car models available in both UK and USA to compare the engines available. Some examples include the Hyundai i30 to the Hyundai Elantra and Elantra GT, Ford Focus & Fiesta, Chevrolet Cruze to Vauxhall Astra, VW Golf. You’ll find their base gasoline engines are much smaller in the UK than in USA. If our government taxed owners based on size of engine and taxed fuel to the point of extremely high prices than we too would have such vehicles. You should also look at the vehicle weight of vehicles today compared to same models in the 80s. Besides growing in size they’ve also grown in weight from suspension and crash safety technology. Base model Golf and Civic of today have more HP than the GTI & Si of the 80s. Today’s non-turbo four cylinders have more HP than V6 cars of the 80s and the turbo 4s of today would beat factory spec V8s of the 80s while also offering much better fuel economy. You look at MPG numbers while some of us look at efficiency for power output. If consumers were willing to deal with 0-60 in over 10 seconds and quarter mile acceleration of over 20 seconds then we too would have high MPG numbers.

Thank you all for excellent explanations concerning the progress of internal combustion engines advances in the last 40 years. Also the personal experiences of those (who have witnessed and contributed to those advances) are much appreciated as well. Lots of professional expertise out there who have contributed to this thread as well. Thank You all. The contributions to the thread leave me with a better understanding of ongoing internal combustion engine innovation and engine efficiency progress during the past 40 years.

The vvt, fuel injection, fuel mapping, turbo's, (OBD1 and 2), air induction, the list go's on. Add to that the modification of gear ratio's with 6 speed plus transmissions, CVT's and drag coefficient's always being improved upon. There have also been some impressive increases in both torque and HP as a result of engine design improvements.

Also mentioned were some comments about subcompacts of Europe lighter cars, requiring lessor size compressors, evaporators and condensers which required not as much HP from the engine as the American's cars dealing with the more extreme climate's in the U.S. Add to that the high safety standards of our country and you can see the a pattern.

One of the many reasons that a our cars are simply bigger. Are our cars less fuel efficient, No. Cars in the U.S. have more stringent crash test requirements, larger air conditioner's requirements, and Interstate highways that require high speed entrances and longer distances traveled commonly in the U.S. The consumer decides what sells here and cars buyers vote with their purchases. The biggest selling cars speak volumes about what direction new technology is heading.

Progress has been made because the cars that got 50 mpg historically were much slower
(0 to 60 MPH )forty years ago. Cars are certainly stronger and engine longevity has also increased.
So what even better engineering will go into the engines of the future? One thing for sure the changes to come will keep happening at an accelerated rate. It's a great time to be around and watch it unfold.

[eaton53]

Originally Posted by corolla5speed

So what even better engineering will go into the engines of the future?

IMO, every ICE will eventually be electrically assisted.
Hybrid at minimum, along with PHEVs and full EVs.

[StealthRabbit]

CVT's have a ways to go... I just turned in a Toyota rental (Corolla) that I could only squeeze 38.5mpg over 3-5 days average. I hate CVT with a passion (Snowmobile tranny). 10 gal tank on Corolla drove me crazy, stopping for gas at 300 miles, when I an not even down to 3/4 tank at 400 miles on my daily driver.

I always request a manual tranny if in Europe. USA rentals have not 'evolved' to allow that option.

Even a Ford Focus AT, I can average over 40 mpg. I hope they do not get CVT's!

[NW4me]

Perhaps this has been mentioned already, but more precise engine manufacturing makes
for reduced compression loss, so more power from the same size engine.
Also, various improvements to diminish internal friction, so again more usable power
from the same displacement.

I think these improvements, along with fuel injection, are the reasons why even a Hemi V-8 in a big car
can get 20 mpg.

[ddm2k]

Originally Posted by StealthRabbit

CVT's have a ways to go... I just turned in a Toyota rental (Corolla) that I could only squeeze 38.5mpg over 3-5 days average. I hate CVT with a passion (Snowmobile tranny). 10 gal tank on Corolla drove me crazy, stopping for gas at 300 miles, when I an not even down to 3/4 tank at 400 miles on my daily driver.

I always request a manual tranny if in Europe. USA rentals have not 'evolved' to allow that option.

Even a Ford Focus AT, I can average over 40 mpg. I hope they do not get CVT's!

Hate hate hate the CVT and any transmission 8 speeds or greater.

Shift shift shift shift shift shift shift to get to interstate speeds.

It would appear that one would spend more time in between gears than actually in them.

Not advocating a 2-speed Powerglide, but let's get real.

[OutdoorLover]

Cars are definitely a lot more fuel efficient than 40 years ago (when comparing apples to apples in terms of vehicle size, weight and performance).

Still, internal combustion engines as well as the transmissions have been evolving for over 100 years, and I think the residual gains left out there to be collected are no longer so great. When you have a modest sized computer controlled direct injected 4-cyl engine with a whiz-bang valve-train, a turbo, and a CVT, efficiency is pretty darned good.

Hybrids, though no longer a pure ICE, can offer a big additional bump - 25-30% higher mpgs, but adoption has been fairly slow so far; we'll see as a new crop of hybrids is around the corner, and some of these are now using the stingier Atkinson cycle. Beyond hybrids are full electric vehicles.

[southernnaturelover]

Originally Posted by ddm2k

Hate hate hate the CVT and any transmission 8 speeds or greater.

Shift shift shift shift shift shift shift to get to interstate speeds.

It would appear that one would spend more time in between gears than actually in them.

Not advocating a 2-speed Powerglide, but let's get real.

I agree. I think 6 speeds is the sweet spot, that’s what my Tundra has and it really doesn’t seem to downshift any more than the 5 speed auto it replaced.



I think one important advancement has been variable valve timing, it has really played a big part in getting more power out of engines. I guess we can thank Honda for that one.

Direct injection has also increased power, but unfortunately it has seemed to hurt reliability in the long run.

[nedergras]

Originally Posted by victimofGM

Just checked the UK Hyundai site. A Hyundai i30 comes with a 1.0L turbo with 118 hp while the same car in USA is 2.0L 148 hp in Elantra sedan). For direct comparison the USA Elantra GT comes with a 2.0L 161 HP base engine.

That 1.0L turbo fuel economy in US MPG is 47. The most efficient USA Elantra is 40 mpg with a 1.4L turbo with 128 HP and 40 MPG HWY & 32 MPG city.

I think America and Canada are the only countries that get Civics with a 2.0 4 cylinder, everywhere else they're 1.0 3 cylinder turbos or 1.5 4cyl turbos. Also Mexico gets the 2.0.