Why isn't the fuel economy better?

[Rayme]

Originally Posted by RaceR

Some info for you US gas guzzling guys and girls! :P

GT86 188g CO2 (combined). That gives it a rating of F. Which basically sucks. This is EU-standard rating system.


The average CO2 emissions of new cars in Norway September 2012 is 125g CO2.
Yeah, I know. The Norwegian population is a drop in the ocean, but tought Id share some numbers either way to put things into perspective.

Here is the Norwegian average CO2 emissions for all car manufacturerers on new cars sold between January-September 2012. Only Porsche and Jeep have an average that is worse than the GT86 (if you look away from a couple of car manufacturers who only sold 1-4 cars).


Here is the average CO2 consumption from low output cars:


I know the stripped out version of the BRZ without LSD "only" have 159g CO2. Which is not bad for a 2l NA car. But with the final ratio of the LSD (big increase in consumption?), and the resistanse of the LSD (a little increase) , and a little extra weight (minimal increase) it goes up to 188g CO2. And by looking at that number, it is not impressive.

Need to see a lightweight 1,6l turbo or smaller displacement engine in this car to improve fuel efficiency.

Emissions are not directly linked to fuel economy, but, good info.

Lean burn engines gave incredible fuel economy, but have alot of emissions.

[RaceR]

Originally Posted by ottopilot

Emissions are not directly linked to fuel economy, but, good info.

Im no expert on the field.
But CO2 emissions are calulated based on an average consumption (of city and highway). They can directly be converted into fuel consumption. (different calculation for petrol and diesel engines).

Basics such as a cold engine having higher fuel emissions, and emissions in general is normal.
Also that engines have different NOX outputs. But for a typical petrol engine car in EU that is about 30mg NOx per km.
Modern diesel engines usually have 120-170 mg NOx per km.

Again those numbers will change, and they used to be worse.
But I would say fuel economy can be linked quite good to emissions. Atleast when comparing modern stock cars.
If you change the catalytic converter, then we have a different case....

[einzlr]

wow, I had no idea Tesla was selling the Roadster outside the US

[einzlr]

Originally Posted by ottopilot

Emissions are not directly linked to fuel economy, but, good info.

Lean burn engines gave incredible fuel economy, but have alot of emissions.

A while back, Dennis Simanaitis wrote an informative article for Road&Track on the trade-off between tuning the fuel/air mixture to optimize for fuel efficiency vs for clean emissions.

[RaceR]

Originally Posted by einzlr

wow, I had no idea Tesla was selling the Roadster outside the US

I believe the 5 million people in Norway make a bigger market for the Model S than the whole US in 2013.
It will cost about between 1/3 or 1/4 of an M5 here.. (Only very rich people can afford new M5)
That car will be huge here, at least if the government will not add special taxes for it.
Starting price of Model S is almost the same as GT86...
yeah, I have actually considered GT86 vs Model S. And almost still am due to the bang for the buck on the Model S..

Edit: Sorry. Norway is the largest market outside the US for Tesla. No other country outside the US have more reservations for the Model S than us. Which is quite extreme consider the low population here..

[carbonBLUE]

Originally Posted by White Shadow

I don't get it, I really don't. These are lightweight cars. They aren't all that powerful or fast. They don't make a lot of power or torque. Yet the fuel economy ratings are lower than some other cars that are 1000 lbs heavier and more powerful & faster.

Am I alone in thinking that these cars should be rated at least 25 city and 35 highway, at the absolute minimum? I mean, a freaking BMW 328i is a boat compared to the FT86, yet it has the same city fuel economy rating and gets 4 more mpg on the highway.

Maybe I'm being too critical, but I honestly thought that such a small and lightweight car would be more fuel efficient, especially with a 2.0 engine that makes modest power.

heres a great example
in my auto frs its rated at 34 highway, i can easily get 46 mpgs at 60-65 mph cruise controlled

in an auto v6 mustang 2013
says 31 mpgs
I have 3 friends with 3.7L mustangs and none of them ore anyone on the mustang forums ever got that number unless they changed the gearing in the back end to a ridiculously large final drive ratio, most of them get 24-25 on the highway at 65 mph...

Its not what the car is rated but what it actually gets... i mess around a lot drifting and i still get 30 mpg average...

[MVJ1975]

Originally Posted by RaceR

I believe the 5 million people in Norway make a bigger market for the Model S than the whole US in 2013.
It will cost about between 1/3 or 1/4 of an M5 here.. (Only very rich people can afford new M5)
That car will be huge here, at least if the government will not add special taxes for it.
Starting price of Model S is almost the same as GT86...
yeah, I have actually considered GT86 vs Model S. And almost still am due to the bang for the buck on the Model S..

The base, cheapest Model S in the US costs twice what the FR-S does. I'm guessing the GT-86 is being hit with some sort of tax or you're getting some sort of subsidy on the Tesla.

[RaceR]

Originally Posted by MVJ1975

The base, cheapest Model S in the US costs twice what the FR-S does. I'm guessing the GT-86 is being hit with some sort of tax or you're getting some sort of subsidy on the Tesla.

No VAT (25%) on electric vehcles and no insane car taxes (based on CO2, HP NOx and weight). There is no sort of subsidy, at least if don't consider no VAT a subsidy.

GT86 gets very high CO2 taxes and high HP taxes + VAT.
42% av the G86s price are taxes..

It would be much better if Toyota managed to get the rated CO2 emissions (fuel consumption) as low as possible.
BMW is very good at underrating hp and torque on their modern engines. And they seem to be good at overestimating how low the the emissions are (like most others) compared to what you would get with real life driving. That is a huge advantage in terms of taxes here.
Toyota need to learn from the germans in my opinion. Toyota seem to maybe underrate the fuel efficiency a little, and hot have any extra power compared to the paper numbers. The opposite would be much better with the Norwegian tax system.

The 184HP engine in the Cooper S gets half the taxes compared to the 86s due to the 86s high fuel consumption (CO2). In practice the Cooper S is also more powerful due to its low down torque and since its numbers are underrated. So that engine gives more power at half the taxes (and there are a lot of taxes!)

[RaceR]

The 1.4L in the new Golf looks pretty awesome on paper, and probably in real life too.
114g CO2, 140HP, 250nm @ 1500rpm

More paper numbers:
188g CO2, 3L (I6) turbo, 320hp, 450nm - BMW M135I (manuall, Automatic is 175g CO2)
188g CO2, 2l NA, 200hp, 205nm - GT86/BRZ
131g CO2, 1,6 turbo, 136hp, 220nm - BMW 116I (F20)
136g CO2, 1,6 turbo, 184hp, 240nm - Mini Cooper S

Dyno comparison:
BRZ (green) vs Cooper S made be Perrin on the same dyno, + BMW 116I dyno results hand drawn by me (in yellow) taken from another wheel dyno in Norway. The 116I have about 20% more HP than it should have, and a ton more torque than it should have. Not a very big surprise considering it is a downtuned 118I, and that is almost the same engine as the Cooper S.


(For the record, I own a Cooper S, and test drove 116I and GT86 the same day. My butt dyno says these real life dyno looks pretty right)

Compared to modern turbo engines the numbers from the 86 are not impressive in terms of output vs fuel economy.
And they are even worse when comparing real life power compared to underrated modern turbo engines.. On every day driving- below 5000 RPM a 136hp 116I beats the 200hp 86 with good margin. Compare 4000rpm!
yeah, the character of a 116I is very boring, and the GT86 is fun at high RPM. But that is not the point..

I still desire a GT86, but im not impressed by its efficiency or engine numbers.
Is it because it is a bad NA? No, but modern turbo engines are just very impressive..
The M135I probably have 350 flywheel hp and 500NM from a 3L 6 cylinder engine with same emissions (at least on paper) as the FR-S/BRZ.

You can get this performance (and sound) out if an engine that is more fuel efficient than the FR-S/BRZ!
[ame="http://www.youtube.com/watch?v=bw8_orwXldM&feature=g-hist"]BMW M135i F21 - acceleration 0-250 km/h - YouTube[/ame]

[White Shadow]

Originally Posted by einzlr

Thanks for compiling this information! There's a difference between EPA ratings, which are obtained systematically through a set of well-defined tests, and actual real-world experience. Anyone care to dig up the EPA numbers for the above cars? It would be interesting to compare.

I don't really have the energy right now, but the easiest way to get the EPA fuel economy ratings for all cars is right here:

www.fueleconomy.gov

[White Shadow]

Originally Posted by JohnS_Rosamond

One of the things that I remember reading in one of the recent car magazines was that some of the cars that had high EPA ratings did not actually get those high numbers in real world driving. The article was specifically looking at the cars that stated 40mpg (Elantra, Focus, Cruze?) So, EPA numbers may - in themselves - be a little misleading. Also, EPA regulations changed some years ago so you cannot cross shop "old" EPA ratings and newer ones.

Those who mentioned the Miata. My '03 was rated 22 city/ 28 hwy. My mixed mileage is usually between 26-28mpg. I can get 30 on the highway if I'm not going to fast and I'm not going against a headwind.

I think in the gas wars, gearing is probably the king when it comes down to what your car will actually get while going down the road.

If you go to the site I mentioned about (www.fueleconomy.gov), they do allow you to compare the fuel mileage ratings of old & new cars. For any car that was manufactured before the EPA testing standards were changed, the site will list both "new" and "old" fuel economy ratings.

[White Shadow]

Originally Posted by fatoni

i suggest you look at what i have written. i never said anything about there being tons of them.

No, I guess you didn't say that. I obviously confused you with Mmnhamsandwich who did say that.

having prius tires doesnt change the size of the contact patch.

Never said it did. But Prius tires are tires meant primarily for fuel mileage, which is what I said. Those tires have a small contact patch, low rolling resistance, and are relatively light weight. All are contributors to helping increase fuel economy.

[White Shadow]

Originally Posted by carbonBLUE

heres a great example
in my auto frs its rated at 34 highway, i can easily get 46 mpgs at 60-65 mph cruise controlled..

Hold on a second.....so you're saying that you can average 35% better fuel economy than your car is rated for on the highway? Seriously? Would you be pissed if I raised the BS flag?

[OrbitalEllipses]

Originally Posted by RaceR

I still desire a GT86, but im not impressed by its efficiency or engine numbers.
Is it because it is a bad NA? No, but modern turbo engines are just very impressive..
The M135I probably have 350 flywheel hp and 500NM from a 3L 6 cylinder engine with same emissions (at least on paper) as the FR-S/BRZ.

You can get this performance (and sound) out if an engine that is more fuel efficient than the FR-S/BRZ!

And it'll cost twice as much. Nice comparison.