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Tesla Full Self Driving (FSD) info - interesting stuff!
james_s:
--- Quote from: bdunham7 on July 02, 2022, 09:59:59 pm ---Large heavy cars with large displacement engines were common 5 decades ago and manual transmissions were impractical and not offered in those models. My first car had a 7.5 liter engine. People just got used to them, I guess. Then when cars got downsized, manuals did make a comeback for a while, but automatics were almost always at least an available option if not the predominate (or only) configuration.
--- End quote ---
There's no technological reason manuals were not offered in many of those. The biggest trucks have always been manual, most are even today. Plenty of big V8 powered muscle cars were available with manual, race cars have always been almost exclusively manual.
CatalinaWOW:
Practicality of transmission was definitely not the reason for automatic adoption in the US. Americans liked them, and the penalty in fuel consumption wasn't enough to drive folks away. I have never seen real numbers, but I would guess that in the auto transmissions of the era the penalty was under 20%, perhaps way under. And that is comparing to an optimally operated manual transmission, something the average driver seldom if ever achieves. By the seventies whatever difference there was started growing smaller as lockup torque converters began being adopted, and currently the advantage goes the other way because the computer and a large number of gears can operate the drive train more optimally than all but the best drivers. Cost of acquisition is another factor in this decision, and initially favored manual transmissions. But as more and more people chose automatics the economies of volume overcame the intrinsically lower cost of manufacture of the manual transmission. Finally, maintenance costs tend to favor automatics in my opinion. Solely because the average driver, and especially the driver who believes he is a king of speed absolutely murders clutches. The manual has no intrinsic defense against this, while automatics do somewhat protect themselves. The manual transmission itself is far cheaper to maintain.
While I learned on a manual, and have driven a wide range of manual gearboxes, including those without synchromesh I definitely prefer an automatic. I drive to get somewhere, and having less to do is a plus for me. I will stipulate that there are those who enjoy shoving levers around. But then there are those who rue the loss of manual spark advance and manual chokes. I enjoy the ability to start on a hill without skillful feathering of the clutch (particularly in a rental or other unfamiliar car). I like not having one hand tied up with a shift lever. It doesn't surprise me that many other people feel the same way.
james_s:
--- Quote from: CatalinaWOW on July 03, 2022, 12:58:26 am ---I have never seen real numbers, but I would guess that in the auto transmissions of the era the penalty was under 20%, perhaps way under. And that is comparing to an optimally operated manual transmission, something the average driver seldom if ever achieves. By the seventies whatever difference there was started growing smaller as lockup torque converters began being adopted, and currently the advantage goes the other way because the computer and a large number of gears can operate the drive train more optimally than all but the best drivers.
--- End quote ---
When I swapped a manual into my mom's 1986 Volvo 240 about 25 years ago the mileage increased from 24mpg to 29mpg so it was pretty significant. My current 1990 740 Turbo went from about 20mpg to 26mpg when I swapped in that and that's without putting any great effort into maximizing fuel economy. The difference was substantial, and the car feels so much more responsive. I don't think the fuel economy gap closed until the mid 2000's and even then a manual will typically do a little better if one knows what they're doing.
Modern manuals pretty much all have automatic hill hold, I could take it or leave it, shifting gears and starting on hills and whatnot is second nature for me, it's like walking, I don't even think about it.
CatalinaWOW:
--- Quote from: james_s on July 03, 2022, 01:35:16 am ---
--- Quote from: CatalinaWOW on July 03, 2022, 12:58:26 am ---I have never seen real numbers, but I would guess that in the auto transmissions of the era the penalty was under 20%, perhaps way under. And that is comparing to an optimally operated manual transmission, something the average driver seldom if ever achieves. By the seventies whatever difference there was started growing smaller as lockup torque converters began being adopted, and currently the advantage goes the other way because the computer and a large number of gears can operate the drive train more optimally than all but the best drivers.
--- End quote ---
When I swapped a manual into my mom's 1986 Volvo 240 about 25 years ago the mileage increased from 24mpg to 29mpg so it was pretty significant. My current 1990 740 Turbo went from about 20mpg to 26mpg when I swapped in that and that's without putting any great effort into maximizing fuel economy. The difference was substantial, and the car feels so much more responsive. I don't think the fuel economy gap closed until the mid 2000's and even then a manual will typically do a little better if one knows what they're doing.
Modern manuals pretty much all have automatic hill hold, I could take it or leave it, shifting gears and starting on hills and whatnot is second nature for me, it's like walking, I don't even think about it.
--- End quote ---
So by your numbers one car was 17% better, the other 23%. Sounds like my 20% guess wasn't too far off.
I am happy that you have no difficulty on hills. Is this true in every new car you get into? When I get into a new manual vehicle it usually takes me a day or two to get used to the different clutch and engine torque characteristics. Did you ever drive a Mazda rotary? I owned one for a a year or two and driving characteristics were totally different than any other car I have owned.
I am also happy to hear that you are one of the superior drivers who can still best a current automatic. I suspect though that the gas mileage for the overall population is better with current automatics. Even though well over three quarters of the population is sure they are better than average drivers.
SilverSolder:
The last generation of big American cars were not that bad on fuel... I have an elderly 6 passenger Buick from 2000, with a V6, it does 35mpg on the highway at a steady 60 - 65. It has an automatic with a lock-up converter, and very tall gearing... It actually gets better mileage on the highway than my Escape hybrid! - obviously once you are in town, things are very different...
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