T-bone Collision

keep in mind the manufacturer tests and supplies the figures, not all get retested by the governing body to confirm, they are know to cheat the system too (VW emissions scandal should ring a bell), unrelated as to whether auto or manual is more efficient but just the general unreliability of the figures either way
True, but the potential for retesting is always there so if they 'cheat' it would have to be done very well and in much the same way that VW did to be successful - and VW ultimately failed in their attempts anyhow. There's is no way to 'retest' real world, self-reported, anecdotal data.
 
they weren't the only ones caught out, just the highest profile I think

I don't think I've ever read a new car review that didn't have something like 'claimed figures and actual figures' mentioned, they never seem to match whatever the manufacturer publishes so I'd only ever consider them as a guide anyway
 
...I'd only ever consider them as a guide anyway
I use them to compare vehicles under the assumption that the testing is constant so if vehicle A tests 2 MPG better than vehicle B it's reasonable to further assume that the same differential would apply to the real world.
 
I use them to compare vehicles under the assumption that the testing is constant so if vehicle A tests 2 MPG better than vehicle B it's reasonable to further assume that the same differential would apply to the real world.

it should, the testing criteria is an established pattern that must be followed, results can still vary due to the dyno itself as not all are calibrated the same, the same vehicle on two different dynos can give different results, I would say within the one manufacturer group though that the tests between various models are likely carried out using the same equipment so are likely to be a more accurate guide as to which models within the brand are more fuel efficient than others
 
You guys can rationalize this every which way to Sunday but the facts show that modern computerized automatic transmissions using more gears at different ratios than older units are as fuel efficient or more than traditional manual transmissions.
 
You guys can rationalize this every which way to Sunday but the facts show that modern computerized automatic transmissions using more gears at different ratios than older units are as fuel efficient or more than traditional manual transmissions.

never said otherwise, the results published between different manufacturers are not going to be an accurate number but a reasonable guide, if talking about the same manufacturer and just the difference between the auto and manual versions of the same vehicle then those are numbers that are more useful and a more accurate reflection of the difference achievable between the different transmission types

if you want to go back 30 years or so in technology to your average 4 speed manual transmission versus the average 3 speed auto transmission of the day which seems to be the type of technology that Nigel is thinking about then sure, the manual transmission had the edge

fast forward to anything recent though where the autos are computer controlled, multi geared, lockup torque converters etc then that's a whole different ball game, the vehicles computer does most of the work and is going to do things more efficiently than is possible for the average driver using a manual transmission
 
never said otherwise, the results published between different manufacturers are not going to be an accurate number but a reasonable guide, if talking about the same manufacturer and just the difference between the auto and manual versions of the same vehicle then those are numbers that are more useful and a more accurate reflection of the difference achievable between the different transmission types

if you want to go back 30 years or so in technology to your average 4 speed manual transmission versus the average 3 speed auto transmission of the day which seems to be the type of technology that Nigel is thinking about then sure, the manual transmission had the edge

fast forward to anything recent though where the autos are computer controlled, multi geared, lockup torque converters etc then that's a whole different ball game, the vehicles computer does most of the work and is going to do things more efficiently than is possible for the average driver using a manual transmission

No you never said otherwise nor did I accuse you of saying so but you've entered this discussion a little late in the game. Regarding, what you mention about the differences between the old days and now is quite true though. Interestingly, the first comparison illustration I posted about the recent model Toyota Tacoma trucks, both the automatic and the manual transmissions have six gears but the automatic has the edge. My real world experience with that truck pretty much matches the posted ratings and that has been confirmed to me by others.

Frankly, I'm a little surprised that anyone would argue over this subject in this day and age especially to this degree but then I have to remind myself about who is doing the arguing here. ;):rolleyes:

FWIW, I love driving manual transmission vehicles, especially in the right car and traditionally would never have it any other way. Times do change however and while I never would have imagined buying a four wheel drive truck with an automatic I just love it. I didn't know what to expect, especially in a vehicle I work hard periodically, hauling heavy cargo, four wheeling out on my property, driving into town in a blizzard or cruising on the highway. The thing takes whatever I throw at it and provides better mileage than my old manual transmission Toyota truck that had half the horsepower and it does so a lot more quietly. It's a six speed but I kind of think of it as an eight speed because of the low gear settings in 4x4.
 
they weren't the only ones caught out, just the highest profile I think

I don't think I've ever read a new car review that didn't have something like 'claimed figures and actual figures' mentioned, they never seem to match whatever the manufacturer publishes so I'd only ever consider them as a guide anyway
Best story I heard on cheating was that since the cars don't actually move during the test, the aerodynamics are not tested, which is why most modern cars don't have particularly good aerodynamics. However the wind resistance is simulated by the dynamometer using a table provided by the manufacturer from a test on a real test track with a real moving car that somewhat resembles a production car, although they probably remove the wipers and mirrors and tape over all the panel gaps, government retests would use the same table. To avoid the possibility that the manufacturer would cheat by always testing downhill and so get better wind resistance figures, the rules say that it has to be tested in both directions along the test track. So one of the manufacturers built a new test track, over the top of a hill, whichever direction they test in, it is up hill during acceleration, then downhill during the measurement!

There are other things that aren't tested at all, for example the steering never moves, hence recent models all have electric power assisted steering that uses zero power during the test but on a real road would be active most of the time, unless you actually encounter a road with zero camber!

One reason that recent USA official figures may favour automatics is that the manufacturers can cheat more with the automatics:

When the Audi starts up, its transmission engages a ‘low CO2' program, shifting gears in such a way as to keep engine revs and emissions artificially low. If the steering wheel is turned more than 15 degrees, the car deactivates the program and shifts in its normal, more pollutant fashion that burns more gas and produces more CO2. Audi figured that the only time the car would run with the steering wheel never moving would be in a lab, on a test bed. This is a similar philosophy to the classic ‘dyno mode’ cheat that kicked off Dieselgate. It’s so simple, and apparently it was enough to get Audis to pass emissions tests in lab situations they might have never passed in real world conditions. The cheat was only implemented on cars with an automatic transmission...
https://jalopnik.com/america-figured-out-a-new-way-audi-cheated-on-emissions-1788630969
 
this is similar to how they cheat the engine power figures, for many years engines were dyno tested with no accessories attached, makes a difference when no AC, alternator, water pump etc is being driven
 
Crash safety ratings are similar. Change the offset or angle parameters 15% and you could get a large difference in results because the design engineers optimize the car for the tests, not for crashes :rolleyes: So test numbers make for comparison at best, not real-world results under all circumstances.

When I was sub-meter in height, the US gasoline dealership "Mobil" used to do real-world "economy runs" every year of many of each years new car models. Each car was driven on real-world roads across America by several different people with hills, curves, rain and dry plus whatever wind happened to be present. And most important, they drove fairly 'normally' instead of doing everything possible to save fuel :D Whereas US car manufacturers once supported this, they began backing away when it became clear that their cars weren't improving in fuel mileage each year and the increasingly common imports could beat the US cars by a huge margin :eek: The important thing here is that anybody could match their numbers- something which is almost impossible to do with today's EPA numbers :( Airlines discovered long ago that letting the computers fly the plane reduced fuel costs significantly, and with fuel being their largest ongoing expense that made for better profits. Nowadays pilots are not allowed to 'hand-fly' without an over-riding reason to do so. The computers are programmed to maximize efficiency and they cannot be beaten at their game. This is the approach car makers should be taking but instead an artificial test is applied and it can be artificially cheated on :mad:

I don't know what "the book" says now, but when I was licensed it was the law that you held the footbrake firmly while stopped in traffic; the parking brake was for parking only. It makes good sense on several counts :cool: First is that it keeps your brake lights on so that others can more easily see that you are stopped. Second it allows instant reaction should you suddenly need to move. Third is that it is holding 4 wheels, not 2, so that if someone hits you from behind it will take twice the force to move your car which also protects others around you. I'm sure other reasons could be found but my last one should be enough on it's own: using the handbrake in traffic is less safe :oops:

I do wish they would teach left-foot braking which is what professional drivers and law enforcement drivers are taught as it allows much better vehicle control and allows for much quicker braking. When I'm in traffic, my left foot is hovering over the brake, heel on the floor and no contact with the pedal- it's become natural to me. That quarter-second time gained has saved my hide numerous times when some idiot jumped in front of me and braked suddenly to make a turn :censored: I can also accelerate more quickly this way too. You lose that advantage with a manual trans :whistle: Fuel mileage and comfort matters but safety always comes first :D

Phil
 
I do wish they would teach left-foot braking which is what professional drivers and law enforcement drivers are taught as it allows much better vehicle control and allows for much quicker braking. When I'm in traffic, my left foot is hovering over the brake, heel on the floor and no contact with the pedal- it's become natural to me. That quarter-second time gained has saved my hide numerous times when some idiot jumped in front of me and braked suddenly to make a turn :censored: I can also accelerate more quickly this way too. You lose that advantage with a manual trans :whistle: Fuel mileage and comfort matters but safety always comes first :Dusing the handbrake in traffic is less safe :oops:

Phil
My preferred method as well.
 
Crash safety ratings are similar. Change the offset or angle parameters 15% and you could get a large difference in results because the design engineers optimize the car for the tests, not for crashes :rolleyes: So test numbers make for comparison at best, not real-world results under all circumstances.

When I was sub-meter in height, the US gasoline dealership "Mobil" used to do real-world "economy runs" every year of many of each years new car models. Each car was driven on real-world roads across America by several different people with hills, curves, rain and dry plus whatever wind happened to be present. And most important, they drove fairly 'normally' instead of doing everything possible to save fuel :D Whereas US car manufacturers once supported this, they began backing away when it became clear that their cars weren't improving in fuel mileage each year and the increasingly common imports could beat the US cars by a huge margin :eek: The important thing here is that anybody could match their numbers- something which is almost impossible to do with today's EPA numbers :( Airlines discovered long ago that letting the computers fly the plane reduced fuel costs significantly, and with fuel being their largest ongoing expense that made for better profits. Nowadays pilots are not allowed to 'hand-fly' without an over-riding reason to do so. The computers are programmed to maximize efficiency and they cannot be beaten at their game. This is the approach car makers should be taking but instead an artificial test is applied and it can be artificially cheated on :mad:

I don't know what "the book" says now, but when I was licensed it was the law that you held the footbrake firmly while stopped in traffic; the parking brake was for parking only. It makes good sense on several counts :cool: First is that it keeps your brake lights on so that others can more easily see that you are stopped. Second it allows instant reaction should you suddenly need to move. Third is that it is holding 4 wheels, not 2, so that if someone hits you from behind it will take twice the force to move your car which also protects others around you. I'm sure other reasons could be found but my last one should be enough on it's own: using the handbrake in traffic is less safe :oops:

I do wish they would teach left-foot braking which is what professional drivers and law enforcement drivers are taught as it allows much better vehicle control and allows for much quicker braking. When I'm in traffic, my left foot is hovering over the brake, heel on the floor and no contact with the pedal- it's become natural to me. That quarter-second time gained has saved my hide numerous times when some idiot jumped in front of me and braked suddenly to make a turn :censored: I can also accelerate more quickly this way too. You lose that advantage with a manual trans :whistle: Fuel mileage and comfort matters but safety always comes first :D

Phil
Funny... I left foot brake more often in a manual than I do in an auto. Granted, that's mostly in a race situation, but still... I learned left foot braking in a manual.

On a somewhat related note, the first Tesla I drove, the owner had it set up for max regenerative braking. So when you let off the throttle it felt like pressing the brakes. So you could drive with one pedal quite effectively. You only needed the brake pedal to come to a complete stop or if you needed to stop faster to avoid something.

PPS: even though that car was "only" a regular single motor P85, using that right pedal was still pretty awesome. :D
 
Best story I heard on cheating was that since the cars don't actually move during the test, the aerodynamics are not tested, which is why most modern cars don't have particularly good aerodynamics. However the wind resistance is simulated by the dynamometer using a table provided by the manufacturer from a test on a real test track with a real moving car that somewhat resembles a production car, although they probably remove the wipers and mirrors and tape over all the panel gaps, government retests would use the same table. To avoid the possibility that the manufacturer would cheat by always testing downhill and so get better wind resistance figures, the rules say that it has to be tested in both directions along the test track. So one of the manufacturers built a new test track, over the top of a hill, whichever direction they test in, it is up hill during acceleration, then downhill during the measurement!

There are other things that aren't tested at all, for example the steering never moves, hence recent models all have electric power assisted steering that uses zero power during the test but on a real road would be active most of the time, unless you actually encounter a road with zero camber!

One reason that recent USA official figures may favour automatics is that the manufacturers can cheat more with the automatics:


https://jalopnik.com/america-figured-out-a-new-way-audi-cheated-on-emissions-1788630969

Conflating the fact that several automobile manufactures got caught using elaborate technical schemes to cheat on emission standards is simply an attempt to muddy the waters and confuse this discussion as it has nothing whatsoever to do with fuel efficiency standards or testing thereof. Fuel efficiency varies widely for all kinds of reasons, even something as simple as tire pressure. The numbers provided by manufacturers are intended as guidelines to consumers looking to make a purchase. Nevertheless, the numbers have been shown to be accurate within a relatively narrow margin. Unlike the emission standards scandal (all from European auto manufacturers BTW) a consumer can easily confirm their own fuel mileage numbers themselves with one or two fill-ups at the gas station. My own testing and testing my friends have done shows the official ratings to be highly accurate with a mile or two per gallon and in some circumstances show the ratings to be conservative. Suggesting that the whole system is rampant with cheating is nothing more a conspiracy theory.

Interestingly, Popular Mechanics Magazine was very skeptical about the 40 mpg claims from various car manufactures and considered them highly suspect. As a result they performed their own extensive testing on the
Hyundai
Elantra and the Ford Focus back in 2012. http://www.popularmechanics.com/car...uth-we-put-40-mpg-claims-to-the-test-6651300/

"For our testing, we specifically didn't want to replicate the way the EPA tests cars. This wasn't just for the sake of being contrarian, but because we wanted to test the cars the way any reader might be able to, which meant driving the cars on the road." ------------ "Counter to our original hypothesis, both cars demonstrated significantly better fuel economy than advertised. Cruising along at 55 mph on the highway, our cars easily cleared 40 mpg and, astonishingly, approached 50.".

The Fuel-Economy Equation
"Many factors determine efficiency—not the least of which is how aggressive you are on the throttle. Still, things like vehicle size, weight, and shape; road friction; outside temperature; aerodynamic drag; and losses in the powertrain all play important roles. Collectively, these factors are known as a vehicle's road load. We've created a simplified version of the road-load equation. Notice how velocity is squared in the equation, meaning each additional mph has a greater impact on your mpg."

roadload.jpg

Expecting the rated numbers posted on the window of a new vehicle in the showroom to be a perfectly accurate representation of real world results at all times is unrealistic and claiming that manufacturers are fudging the numbers is overly simplistic, if not paranoid.

In the United States, fuel efficiency standards are mandated by federal law and covered under the CAFE standards. While much of the data is collected via dynamometer testing submitted by manufactures it is done under strict conditions and the EPA conducts random targeted Certification and Compliance testing of their own on between 15% and 20% of vehicles via the National Vehicles and Fuel Emissions Laboratory.
 
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True, but the potential for retesting is always there so if they 'cheat' it would have to be done very well.

Well no, the cheating doesn't have to be done cleverly, it just has to be consistent. I.E. under the precise conditions given by the test procedure it should give the desired result. And technically, it's not even cheating. It does what it does, under the test conditions. There is plenty of scope for misrepresentative or fraudulent results.

Sent from my SM-G903F using Tapatalk
 
Well no, the cheating doesn't have to be done cleverly, it just has to be consistent. I.E. under the precise conditions given by the test procedure it should give the desired result. And technically, it's not even cheating. It does what it does, under the test conditions. There is plenty of scope for misrepresentative or fraudulent results.

Sent from my SM-G903F using Tapatalk
Like VW did?
 
Like VW did?
Yes, but their intent to deceive was so blatant once it was revealed, that they wouldn't have dared argue that technically their cars passed the tests! :eek: It would have just dug them in deeper.
 
Conflating the fact that several automobile manufactures got caught using elaborate technical schemes to cheat on emission standards is simply an attempt to muddy the waters and confuse this discussion as it has nothing whatsoever to do with fuel efficiency standards or testing thereof.
It always surprises me that the amount of CO2 released by burning fuel "has nothing whatsoever to do" with the amount of fuel burned when the car manufacturers release their "government" emissions figures!

If you look at the chemistry of a really simple fuel:
"One molecule of methane combined with two oxygen molecules react to form a carbon dioxide molecule and two water molecules"
it appears that CO2 emissions should be directly related to fuel efficiency. Petrol may be a little more complicated, but it is still a case of the more you burn the more CO2 you will get, unless you are a car manufacturer!
 
It always surprises me that the amount of CO2 released by burning fuel "has nothing whatsoever to do" with the amount of fuel burned when the car manufacturers release their "government" emissions figures!

If you look at the chemistry of a really simple fuel:
"One molecule of methane combined with two oxygen molecules react to form a carbon dioxide molecule and two water molecules"
it appears that CO2 emissions should be directly related to fuel efficiency. Petrol may be a little more complicated, but it is still a case of the more you burn the more CO2 you will get, unless you are a car manufacturer!

Ever since you made the erroneous claim the manual transmissions get better mileage than modern automatic transmissions you've repeatedly attempted to support your claim with all sorts of unrelated distractions and obfuscations such as the infamous emissions testing scandal.

And indeed the emissions testing scandal perpetrated by VW and others "has nothing whatsoever to do" with real world fuel mileage results even as you continue to promote this myth with this BS molecular example. Obviously there is a relationship between fuel combustion and carbon emissions but the simple fact is that the falsified emissions numbers were achieved via software manipulated engine performance which is not germane to your simple physics example.

Of course, extracting a partial quote from my actual statement is another one of your obfuscations and misrepresentations. The full quote of what I said was, "This has nothing whatsoever to do with objective, scientific testing done by government organizations and other authoritative sources who are not associated with manufacturers."
 
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