Author Topic: Insane overengineering of a car headlight  (Read 18011 times)

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Offline Someone

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Re: Insane overengineering of a car headlight
« Reply #100 on: March 31, 2022, 12:28:39 am »
It's a bit damning to effectively say it's someone elses tough shit if you ever make a mistake. Or they make a mistake and you made matters worse than they should have been.
Hence strict liability being an interesting perspective, you choose to drive a car that is more dangerous, then you can pay for any consequences.

I submit to your honour that if the defendant had walked to the shops any resulting collision would have been of trivial consequence, but they chose to transport in a two ton sharp metal box which horribly injured me.
 

Offline james_s

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Re: Insane overengineering of a car headlight
« Reply #101 on: March 31, 2022, 01:12:20 am »
Hence strict liability being an interesting perspective, you choose to drive a car that is more dangerous, then you can pay for any consequences.

I submit to your honour that if the defendant had walked to the shops any resulting collision would have been of trivial consequence, but they chose to transport in a two ton sharp metal box which horribly injured me.

It already is. If you injure or kill somebody you are held responsible, if it is done through negligence you can be charged with vehicular manslaughter, it's a serious crime.

I expect the same of others as they expect of me. I pay attention to what I'm doing and I try not to hit people when I'm driving. As a pedestrian I pay attention to where I am and try to stay out of the path of vehicles. This is really not that hard, no matter how much we mandate ugliness in cars in the name of pedestrian safety it is still far better to focus that energy on preventing collisions. If people would just put their damn mobile phones down and watch where they're going, whether driving or walking it would go a long way toward reducing the number of injuries and deaths. Instead we have the tail trying to wag the dog, adding all sorts of band-aids on top of the symptom rather than focusing on the cause. The vast majority of vehicle-pedestrian collisions are very easily prevented. They are the result of people simply not paying attention.
 

Offline james_s

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Re: Insane overengineering of a car headlight
« Reply #102 on: March 31, 2022, 01:15:50 am »
No-one is perfect. In other fields you would be only too happy to take precautions just-in-case, and mostly because it's you that's at risk. It's a bit damning to effectively say it's someone elses tough shit if you ever make a mistake. Or they make a mistake and you made matters worse than they should have been.

Nothing is perfect, ever, life is full of risks, people die every single day, it is just a fact. Practical issues aside, I would be willing to wager that installing a mobile phone jammer in a car would do more to help pedestrian safety than installing rounded bumpers and a sloping hood. It's all kind of moot anyway with the massive SUVs that everyone is driving now. It doesn't matter what shape you make the front when the hood is practically at shoulder height.
 

Offline Someone

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Re: Insane overengineering of a car headlight
« Reply #103 on: March 31, 2022, 03:24:11 am »
Hence strict liability being an interesting perspective, you choose to drive a car that is more dangerous, then you can pay for any consequences.

I submit to your honour that if the defendant had walked to the shops any resulting collision would have been of trivial consequence, but they chose to transport in a two ton sharp metal box which horribly injured me.
It already is. If you injure or kill somebody you are held responsible, if it is done through negligence you can be charged with vehicular manslaughter, it's a serious crime.
Except when you look at what actually happens, drivers kill or injure pedestrians and insurance covers it (mandatory/public insurance in many/most countries). They don't see the individual cost of their choices as its averaged across the population, just as mandatory safety requirements are pushed onto that same population. We don't have radically different costs for insurance based on how "good" the driver is or how safe their vehicle is, and if it does go to court a driver isnt grilled on their choice to buy/drive a "truck" vs a small city car, they get treated the same.

Real world:
Sixty percent of the 238 motorists found to be at fault or suspected of a crime faced no criminal charges during the five-year period, CIR found in its analysis of thousands of pages of police and court records from Alameda, Contra Costa, Santa Clara, San Mateo and San Francisco counties.

When drivers did face criminal charges, punishment often was light. Licenses rarely were taken away. Of those charged, less than 60 percent had their driving privileges suspended or revoked for even one day, an automatic penalty in drunk driving arrests.
Caught for drink driving (or speeding) thats an automatic fine/suspension in many jurisdictions despite being a victimless crime, but kill someone, meh they'll get over it.
 

Online tom66

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Re: Insane overengineering of a car headlight
« Reply #104 on: March 31, 2022, 07:48:24 am »
Frankly I don't care about pedestrian safety. I'll stay off of the sidewalks, people should stay out of the road. If everyone just watched where they were going and paid attention this wouldn't be such an issue. The goal should be to not hit pedestrians, not to try to make cars less likely to injure them when they do hit.

What about children? The blind? Or just people who are distracted? The fact is, despite the best efforts of drivers and pedestrians, there are about 300,000 pedestrian deaths per year. 
 

Online coppice

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Re: Insane overengineering of a car headlight
« Reply #105 on: March 31, 2022, 06:49:10 pm »
Except a comparable market with the Volvo XC60 (not a small vehicle) has a more rounded front and almost identical impact point as your 740 example. Every single aspect of their front designs is optimised in the never vehicle to reduce the forces in the current safety tests, for pedestrians: Head Impact (rounded sloped bonnet and deformation), Upper Leg Impact (rounded impact point below hip), Lower Leg Impact (no protruding bumper).
Depends which XC60 you are looking at. The front of the older one, that was replace in 2017, has a lowish front edge to the bonnet, and is very much rolled off. The newer one has a much higher and flatter front. With a 740 the first point of impact is the big black bumper, and as they pushed the pedestrian over they meet a sloped off bonnet which will catch them. The smaller XC40 has an even higher bonnet and squarer front than the XC60 or XC90. Its so tall its the total height of a small child, and will hit one like a battering ram. Besides safety issues, its not clear to me how these newer designs achieve decent results in drag tests.
 

Offline Someone

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Re: Insane overengineering of a car headlight
« Reply #106 on: March 31, 2022, 10:34:02 pm »
Except a comparable market with the Volvo XC60 (not a small vehicle) has a more rounded front and almost identical impact point as your 740 example. Every single aspect of their front designs is optimised in the never vehicle to reduce the forces in the current safety tests, for pedestrians: Head Impact (rounded sloped bonnet and deformation), Upper Leg Impact (rounded impact point below hip), Lower Leg Impact (no protruding bumper).
Depends which XC60 you are looking at. The front of the older one, that was replace in 2017, has a lowish front edge to the bonnet, and is very much rolled off. The newer one has a much higher and flatter front. With a 740 the first point of impact is the big black bumper, and as they pushed the pedestrian over they meet a sloped off bonnet which will catch them. The smaller XC40 has an even higher bonnet and squarer front than the XC60 or XC90. Its so tall its the total height of a small child, and will hit one like a battering ram. Besides safety issues, its not clear to me how these newer designs achieve decent results in drag tests.
I did look at the currently available one (which scores better euroncap pedestrian safety than the older lower/rounder looking model) with the scale comparison attached below. Panel give/softness and "catching" the pedestrian becomes the game, which these modern cars do better.

Also, if you want to go like for like against a 740 that would be something like a Volvo V60, rather than a soft roader. But the current V60 model does slightly worse on the euroncap pedestrian safety measure than the current XC60 !
 

Offline SilverSolder

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Re: Insane overengineering of a car headlight
« Reply #107 on: April 02, 2022, 11:20:51 am »
[...]
Caught for drink driving (or speeding) thats an automatic fine/suspension in many jurisdictions despite being a victimless crime
[...]

Is it really victimless, though?  Speeders/drinkers are subjecting others to increased risk....  so it is only victimless until it isn't?
 

Offline Someone

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Re: Insane overengineering of a car headlight
« Reply #108 on: April 02, 2022, 01:44:16 pm »
[...]
Caught for drink driving (or speeding) thats an automatic fine/suspension in many jurisdictions despite being a victimless crime
[...]
Is it really victimless, though?  Speeders/drinkers are subjecting others to increased risk....  so it is only victimless until it isn't?
Yes, victimless until it isnt, but even with the victim obvious, fault found, why do car vs pedestrian collisions have so few penalties applied?

Answer... speeding/drink driving is cheap/easy to prove and prosecute, so gets aggressively targeted for enforcement and penalties. Sad but true.

Australian (state of Victoria) example, several victimless crimes:
25km/h over the speed limit (in any speed zone) $500 fine and mandatory 3 month license suspension, unable to be appealed or waived on hardship grounds etc.
Failing to stop at a school children's pedestrian crossing when people are on the crossing, $454 fine
Failing to give way (or stop if required) at a level crossing, $909 Fine

won't someone think of the children trains!

One of those is an immediate and present danger to other (vulnerable) road users, but has the smallest fine! Train vs car, train wins. Car vs child.....
 

Offline PlainName

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Re: Insane overengineering of a car headlight
« Reply #109 on: April 02, 2022, 01:54:59 pm »
Quote
why do car vs pedestrian collisions have so few penalties applied?

It's not often a car mows down a pedestrian (at least, when they do the penalty tends to significant and the court case very public). More often, I suspect, the pedestrian gets in the way of the car. While peds have right of way over cars, physics says peds can get out of the way easier, so there's a limit to how much stupidity they can get away with.

A better question may be why cyclists get away with so much law breaking. Mostly that's 'victim-less' but only because peds can jump out of the way easier. Quite often on my walks around here I find myself stepping into the road so a bloody cyclist can zoom by on the footpath.
 

Offline MadScientist

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Re: Insane overengineering of a car headlight
« Reply #110 on: April 02, 2022, 02:55:09 pm »
Interesting , but has little to do with head light design.
EE's: We use silicon to make things  smaller!
 
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Offline Someone

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Re: Insane overengineering of a car headlight
« Reply #111 on: April 02, 2022, 11:26:01 pm »
[...]
Caught for drink driving (or speeding) thats an automatic fine/suspension in many jurisdictions despite being a victimless crime
[...]
Is it really victimless, though?  Speeders/drinkers are subjecting others to increased risk....  so it is only victimless until it isn't?
Yes, victimless until it isnt, but even with the victim obvious, fault found, why do car vs pedestrian collisions have so few penalties applied?
It's not often a car mows down a pedestrian (at least, when they do the penalty tends to significant and the court case very public). More often, I suspect, the pedestrian gets in the way of the car. While peds have right of way over cars, physics says peds can get out of the way easier, so there's a limit to how much stupidity they can get away with.
I shall simply refer you right back to the reference you separated that quote from:

Real world:
Sixty percent of the 238 motorists found to be at fault or suspected of a crime faced no criminal charges during the five-year period, CIR found in its analysis of thousands of pages of police and court records from Alameda, Contra Costa, Santa Clara, San Mateo and San Francisco counties.

When drivers did face criminal charges, punishment often was light. Licenses rarely were taken away. Of those charged, less than 60 percent had their driving privileges suspended or revoked for even one day, an automatic penalty in drunk driving arrests.
Caught for drink driving (or speeding) thats an automatic fine/suspension in many jurisdictions despite being a victimless crime, but kill someone, meh they'll get over it.
Those are the cases of people killing pedestrians because of their driving, being at fault, and charged for some offence.

Deaths, not injuries, not near misses, cases of people being killed.

The approximately 50% of pedestrian deaths that could not attribute fault to the driver(s), removed from the above.

Where fault could be attributed to the driver 60% had no action taken against them. I see you've killed a pedestrian and were at fault, please dont do it again.

A better question may be why cyclists get away with so much law breaking. Mostly that's 'victim-less' but only because peds can jump out of the way easier. Quite often on my walks around here I find myself stepping into the road so a bloody cyclist can zoom by on the footpath.
Probably because the road safety figures show that cyclists running into things cause so little damage/injury/deaths compared to other vehicles? Orders of magnitude less.
 

Offline PlainName

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Re: Insane overengineering of a car headlight
« Reply #112 on: April 03, 2022, 12:39:12 am »
Quote
I shall simply refer you right back to the reference you separated that quote from:

I didn't separate the quote from the bit you highlight - you did, as you show in that quote!

Nevertheless, unless we want every post to quote everything that went before, some trimming is necessary. One has to assume that readers of the thread have, well, read the thread so know what it's about and what went before. The particular thing that I am commenting on is what I quote. That will necessarily skip a lot of history, but it is all there in the thread, all pre-read, all known. Nothing is being deliberately left out to obscure anything - if I meant to do that I wouldn't  have quote anything at all.

Quote
Where fault could be attributed to the driver 60% had no action taken against them.

OK.

Quote
Probably because the road safety figures show that cyclists running into things cause so little damage/injury/deaths compared to other vehicles?

Well, cyclists do kill pedestrians, and I suspect that mostly cyclists are hit'n'run and untraceable. However, the point is that they break the law, and that's the actual arbiter of these things.
 

Offline Someone

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Re: Insane overengineering of a car headlight
« Reply #113 on: April 03, 2022, 02:01:25 am »
Quote
Where fault could be attributed to the driver 60% had no action taken against them.
OK.
Quote
Probably because the road safety figures show that cyclists running into things cause so little damage/injury/deaths compared to other vehicles?
Well, cyclists do kill pedestrians, and I suspect that mostly cyclists are hit'n'run and untraceable. However, the point is that they break the law, and that's the actual arbiter of these things.
You're tying to join things that are not equivalent: yes cyclists have and will kill pedestrians (at a tiny rate compared to cars, even when accounting for differing rates of exposure/interaction). But what rate are they prosecuted at for those occurrences? higher or lower than car drivers?

You said:
It's not often a car mows down a pedestrian (at least, when they do the penalty tends to significant and the court case very public).
Which was already shown to be incorrect by the quote you left out of your reply. It happens often, and most drivers dont receive significant penalties. Just look at the numbers:
https://www.bts.gov/content/transportation-fatalities-mode
2020: US 38,680 road deaths, 16% of which were pedestrians!
https://revealnews.org/article/bay-area-drivers-who-kill-pedestrians-rarely-face-punishment-analysis-finds/
Most drivers are not charged even if at fault (already quoted in this thread for those who cant be bothered to read links).

Or, are you trying to argue rates of prosecution for victimless crimes by car drivers and cyclists should be equally high? (and/or equally severe?) Which does not make sense when the outcomes/results of those different modes of transport are so different. Most jurisdictions have lower fines/penalties for victimless crimes committed by cyclists compared to cars, which in turn have lower fines/penalties compared to heavy vehicles. Acknowledging the differing risks.
 

Offline Halcyon

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Re: Insane overengineering of a car headlight
« Reply #114 on: April 03, 2022, 07:28:57 am »
Bah! We don't need all of these things... The old way was cheaper and simpler.

Safety Glass - Non laminated was cheaper
Fuel injection - Carbs were great just a simple mechanical device, none of these new fangled computers telling MY engine how to run!
Seat belts - Just adds cost and besides isn't it safer for the passengers to be thrown clear of the wreck?
Airbags - It's a plot to sell more airbags after a crash by the automotive cabal!
Crumple Zones - Who needs all of that complicated engineering and fancy materials. I want my engine to pushed into the passenger compartment after the crash, it's faster to check for damage that way.
Radial Tires - Man give me back my bias-ply retreads, another conspiracy!
Anti-lock brakes - Again with the computers? My old non-power assisted drums worked fine.
Power steering - Just more over-engineered extras I get a free workout when parking!
etc. etc. etc...

Seriously the only person who would complain about modern headlights is someone who has never driven a car with them.

You can add automatic versus manual transmission to that list these days. I know there are purists out there who will argue that manual transmissions give them "greater control" over the vehicle, which is just bollocks in my eyes, but the fact remains, a well designed modern automatic transmission is better than old manual boxes in every way, including fuel economy.
 

Online tom66

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Re: Insane overengineering of a car headlight
« Reply #115 on: April 03, 2022, 09:34:50 am »
You can add automatic versus manual transmission to that list these days. I know there are purists out there who will argue that manual transmissions give them "greater control" over the vehicle, which is just bollocks in my eyes, but the fact remains, a well designed modern automatic transmission is better than old manual boxes in every way, including fuel economy.

Indeed.  I was helping my fiancé prepare for her driving test recently, and there's a great deal in the theory test that is completely irrelevant to anyone who doesn't drive a manual -- and really does not make me miss them!  "Select a low gear going down hill", "use the engine for braking", "use a higher gear in snow", "careful when you downshift to avoid damage to the engine" etc.  She's been learning in my hybrid, it's almost too easy.  Electronic parking brake, hill hold, regen braking, cruise control, and ridiculously easy to park on electric-only mode as you can move it about 1 cm at a time if you need to. 
 

Offline PlainName

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Re: Insane overengineering of a car headlight
« Reply #116 on: April 03, 2022, 11:04:02 am »
Quote
Just look at the numbers:
https://www.bts.gov/content/transportation-fatalities-mode
2020: US 38,680 road deaths, 16% of which were pedestrians!

Doesn't tell us anything we want to know. Yes, it gives absolute numbers but doesn't say how or why they occured. The explanation even cautions against comparing across categories.

Quote
Or, are you trying to argue rates of prosecution for victimless crimes by car drivers and cyclists should be equally high?

I am saying that cyclist naughtiness is no less of a victimless crime than drink-driving, and that the chance of a cyclist being prosecuted for breaking the law is much lower than for a car driver.
 

Offline JPortici

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Re: Insane overengineering of a car headlight
« Reply #117 on: April 03, 2022, 12:58:09 pm »
You can add automatic versus manual transmission to that list these days. I know there are purists out there who will argue that manual transmissions give them "greater control" over the vehicle, which is just bollocks in my eyes, but the fact remains, a well designed modern automatic transmission is better than old manual boxes in every way, including fuel economy.

I have yet to see one automatic transmission that doesn't add at least 0.5l/100km
if you can kindly suggest which you think are better than manual stick in every way including fuel economy i'll try and make some tests... i know for sure it's not those from VAG or FCA (thought they have better driving profiles in alfa romeo). I hear mixed reports from clients on mercedes but i don't have direct experience so i think in the end it's just a matter of getting used to things regarding manual vs automatic.

Though while we're at it, cars already have tilt sensors so they should know they don't have to keep going to a higher gear when on a steep ascent or descent. Even in """manual""" at some point they take over, screw that i'll be a grumpy stick driver for as long as i can.
 

Online coppice

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Re: Insane overengineering of a car headlight
« Reply #118 on: April 03, 2022, 01:14:42 pm »
You can add automatic versus manual transmission to that list these days. I know there are purists out there who will argue that manual transmissions give them "greater control" over the vehicle, which is just bollocks in my eyes, but the fact remains, a well designed modern automatic transmission is better than old manual boxes in every way, including fuel economy.
In daily use a good automatic performs better, but the manual version of a car is usually cheaper to buy. There are some weird exceptions with expensive sports cars, where the automatic is cheaper, but they are minor exceptions.

 

Online Monkeh

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Re: Insane overengineering of a car headlight
« Reply #119 on: April 03, 2022, 02:31:39 pm »
You can add automatic versus manual transmission to that list these days. I know there are purists out there who will argue that manual transmissions give them "greater control" over the vehicle, which is just bollocks in my eyes, but the fact remains, a well designed modern automatic transmission is better than old manual boxes in every way, including fuel economy.

They're more predictable - an auto requires a little learning curve as to when it shifts or you can get some surprises. Also, they teach you to think ahead. Otherwise, most people are incapable of driving manuals efficiently, so apart from reliability (where they almost always win), there's really no advantage.

I have yet to see one automatic transmission that doesn't add at least 0.5l/100km
if you can kindly suggest which you think are better than manual stick in every way including fuel economy i'll try and make some tests... i know for sure it's not those from VAG or FCA (thought they have better driving profiles in alfa romeo). I hear mixed reports from clients on mercedes but i don't have direct experience so i think in the end it's just a matter of getting used to things regarding manual vs automatic.

DCTs are quite capable of being more efficient than manuals in the hands of the average driver - none of the usual auto losses, and you take the incompetent person out of the loop (and replace them with engineers who don't drive real roads, but that's another argument).
 

Online tom66

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Re: Insane overengineering of a car headlight
« Reply #120 on: April 03, 2022, 04:30:19 pm »
An automatic dual-clutch transmission is just as efficient as a manual transmission.  Arguably it is even more efficient because it can swap gears more quickly due to the built-in rev-matching, which leads to less time when the clutch is slipping or when no power is applied (fuel burn but with no output.)  That's especially important for city driving, but when on the highway roughly all automatic and manual transmissions behave similarly, due to most modern automatic transmissions having a lockout for the torque converter.
 

Offline tooki

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Re: Insane overengineering of a car headlight
« Reply #121 on: April 03, 2022, 07:21:02 pm »
You can add automatic versus manual transmission to that list these days. I know there are purists out there who will argue that manual transmissions give them "greater control" over the vehicle, which is just bollocks in my eyes, but the fact remains, a well designed modern automatic transmission is better than old manual boxes in every way, including fuel economy.

I have yet to see one automatic transmission that doesn't add at least 0.5l/100km
Then you haven’t looked at cars in a very long time, and/or haven’t looked carefully enough.

It’s honestly kind of hard to compare with most cars, because they often don’t let you choose the transmission without also changing a bunch of other stuff at the same time, whose weight differences invalidate the transmission comparison.

But for example, in the BMW 1 series, where you actually can choose multiple engines and transmissions independently, only on the 116d does the manual transmission potentially save fuel. And I say potentially, because only one end of the consumption range changed, and only by 0.1L/100km. On every other engine type, choosing automatic either has no effect whatsoever, or reduces fuel consumption.

This is how it’s been for many years now.

The reason manual transmissions used to be so much more efficient in the past is because they had more gears than automatics. (E.g. in the 80s, a compact car might have a 5-speed manual, but only a 3-speed automatic.) But we now generally have the same number of gears in an automatic (6 being really common now), and a smart computer deciding when to switch. That computer will, on average, do better at switching gears than an average driver.
 
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Offline tooki

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Re: Insane overengineering of a car headlight
« Reply #122 on: April 03, 2022, 07:25:24 pm »
DCTs are quite capable of being more efficient than manuals in the hands of the average driver - none of the usual auto losses, and you take the incompetent person out of the loop (and replace them with engineers who don't drive real roads, but that's another argument).
What a silly statement. Of course they drive on real roads. But if they programmed the transmission ECU to behave the way they’d like, the car would never meet its emissions and fuel efficiency targets. And that’s why we have the switch to choose between eco, standard, and sport modes: the first one for advertisements, the second as a happy compromise, and the third “this is how we’d like it to behave if fuel consumption were no object”.
 

Online Monkeh

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Re: Insane overengineering of a car headlight
« Reply #123 on: April 03, 2022, 07:56:44 pm »
DCTs are quite capable of being more efficient than manuals in the hands of the average driver - none of the usual auto losses, and you take the incompetent person out of the loop (and replace them with engineers who don't drive real roads, but that's another argument).
What a silly statement. Of course they drive on real roads. But if they programmed the transmission ECU to behave the way they’d like, the car would never meet its emissions and fuel efficiency targets. And that’s why we have the switch to choose between eco, standard, and sport modes: the first one for advertisements, the second as a happy compromise, and the third “this is how we’d like it to behave if fuel consumption were no object”.

I was not suggesting they don't feel good - rather that they make inferior choices for fuel efficiency when confronted with real world hills, not idealised test tracks and driving around Heathrow airport. However, they're still far better than the average driver.
 

Online tom66

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Re: Insane overengineering of a car headlight
« Reply #124 on: April 03, 2022, 08:14:55 pm »
The reason manual transmissions used to be so much more efficient in the past is because they had more gears than automatics. (E.g. in the 80s, a compact car might have a 5-speed manual, but only a 3-speed automatic.) But we now generally have the same number of gears in an automatic (6 being really common now), and a smart computer deciding when to switch. That computer will, on average, do better at switching gears than an average driver.

This is really important.  On my Golf, doing 70 mph (~120 km/h) up a modestly steep hill the transmission shifts from 6th to 5th.  You can happily manually switch it back to 6th and the car runs fine, but the fuel consumption is noticeably higher (~5-10%).

Most drivers would say in 6th because the "highest possible gear is usually the best for fuel economy" in car mythology, but of course the ECU has a precise mapping of fuel burn vs torque vs engine speed, and it knows it can still provide the required torque in that gear whilst lowering fuel burn, despite increasing engine RPM.

 
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