An automatic transmission is effectively decoupled when the engine is off despite being left in drive. Without the engine spinning, there's no functioning torque converter. So the most ubiquitous ICE configuration, the auto with a torque converter, defaults to a neutral equivalent when the engine is off and the operator doesn't explicitly put the trans in park.
I never understood how to use automatic transmission in snowy/icy conditions. To me it's basically a lottery. With manual transmission and clutch I can actually recover from a slide almost immediately (the moment you start sliding you disengage transmission right away with clutch and do initial correcting maneuver which you cut short the moment you feel any kind of traction in order not to oversteer; it takes some practice on each car but you can try it on empty parking lots during winter nights). This is not possible with automatic transmission, the neutral gear still drags wheels, driving them to slide. Of course, if you have a 300+hp engine and are a race driver, you might try to correct it using full throttle, but don't try that with a normal car unless you want to massively increase your chance of hitting traffic.
Most EV conversions start with a manual transmission car and leave the transmission in, only because it's easier that way. (Just need an adapter plate to replace the ICE rather than replacing the whole gear box, etc.)
So in those cases, people do sometimes fiddle with gears while driving, mainly for fun I guess; but most often they just leave it in 3rd and drive that way.
This is the same experience one has with an ICE engine and manual gear box at higher RPM. Much easier to drive aggressively in that mode for reasons you state.
Most EV conversions end up keeping the manual gear box because it's simply easier to build an adapter plate for the motor transmission interface than it is to build out a whole new gearbox replacement.
From what I've seen it's fine, you can choose which gear to shift to and leave it there. Cold start from 5th gear. Can even be fun to play with the gear ratios, apparently. But it is another point of failure.
One of the things holding me off from attempting an EV conversion on my old Saab 900 sitting in my shop is that the gear box in it is notoriously brittle and would break even with the torque from the (turbo) gas engine that it shipped with.
> The only real advantages afaik in ICE are better torque control and engine braking
I'd argue the majority of manual fans are into them not for any utilitarian reason, rather it's all about the enjoyment that comes from controlling a fun (i.e interesting powerband, characterful sound) engine with a satisfying shifter. Think of it like playing a musical instrument.
I highly doubt manuals will catch on for EVs because the electric motors are super smooth and their torque makes gears irrelevant (the Porsche Taycan being an outlier here).
I think you make some very valid points. The last Model 3 I spent significant time in did have that general responsiveness to acceleration that you mention, except off the line. I would put my foot to the floor and it would take at least half a second to start moving. I will add the caveat that this was a Hertz rental, so provenance and history unknown.
And I will admit my ICE experience recently is with higher performance cars (my daily driver is an RS 5, which is very much designed to be street and track), where the transmission is absolutely responsive (I think the clutch time was in the 90ms range?). And it seems most ICE CVTs (which I thought would be free from this issue) are optimized for economy rather than response.
> how the gear change from forward to reverse is a flick of the wrist and so on
This is pretty common in performance ICEs. In my car, the gearstick sits in a "neutral" position, and you poke it forward (it returns to neutral) to go into reverse, and pull it momentarily back to go into drive (if you're actually wanting to change gears manually you push it momentarily to the side, and then it functions as a sequential shifter, or of course you have the flappy paddles).
I do appreciate your insights, different perspectives are always good!
Indeed, and as I understand it, there's a mechanism in a modern transmission that disables the torque converter when cruising, further improving efficiency.
Over the course of my life, I've noticed a remarkable improvement in the behavior of automatic transmissions, going from "jerky" to "smooth" for lack of better terms. While overseas last year, I drove a large Mercedes van that even sensed when I was descending a hill, and downshifted the way I would have done it in a stick shift car.
I have read several reviews where people comment that, "driving is way better without the complications of an ICE and a transmission between you and the road". Instant torque changes your relationship with speed: it is ground, tires, suspension, torque and you. Before, there was a complicated interplay of RPMs, turbo spin up, clutch adjustment, gear ratios, etc between you and the suspension.
I mean, you can still shift gears in an automatic car. I used to do it all the time when I lived in a snowy, hilly city. I've never in my life seen an automatic where the only options were drive, reverse, neutral, and park. There's always some amount of control, even if it's only 1/2/3.
Edit: Upon reflection, I assume your comment meant that newer cars will somehow use engine braking themselves. Since electric brake systems are rare in ice cars, would this be referring to cruise control features?
I doubt it'd be much better than any manual car reving up to 4000 RPM and then dropping the clutch. You can squeal the wheels of even low-power engines with that technique.
Frankly, zero-to-sixty in 6 seconds WITHOUT shifting and with 100% standing torque is kind of... awful actually. I suspect the opposite, when a ICE engine hits 4000 to 6000 RPM and the torque kicks in, you'll be accelerating far stronger than the smooth acceleration a Model 3 will give you.
Consider a jerky zero-to-sixty with three gear shifts on your typical manual car (say... Ford Focus ST or RS), in contrast to the smooth acceleration from like a Nissan or a Subaru WRX. You definitely feel more G forces from the Focus, while the WRX only beats the other car because the CVT engine never has to "stop" for the gearshift.
Similarly, I'd expect the smooth acceleration on the Model 3 to have less peak G-forces than a manual car. It will happen to be a smooth and constant acceleration, but there's a HUGE difference in Model 3 vs Model S acceleration. And I hope people aren't getting their hopes up.
Racing divers would shift exactly like automatic because they need to tease the best possible acceleration out of a given engine configuration.
Day to day driving is wildly different from that, there are only very few situations where people come anywhere close to the maximum acceleration their car would offer. With manual transmission, you can attain submaximal acceleration by flooring the throttle in a low gear. This is much more fuel efficient than getting the same amount of acceleration with a throttled engine at higher rpm. Automatic transmissions make that more difficult or even impossible (depending on implementation).
Worst case: people are unhappy with the acceleration they can get at low rev, because the transmission only allows low rev at throttled state and they don't consider it socially acceptable to rev up. The engine would be capable of much more torque at the desired rpm, if only the throttle could be opened without the transmission shifting for higher rpm. Next time they will get a bigger engine that will be throttled even more. ICE inefficiency rises with high rpm and closed throttle (opening the throttle raises power output more than consumption). Ideal ICE efficiency is when the gear is selected so that torque at open throttle matches the power demand. Manual can come much closer to that than automatic. (Unfortunately, many people don't know that and drive manuals like automatic, e.g. never at really low rpm, never at really open throttle, because they think that opening the throttle would be wasteful)
Engine breaking isn’t as effective in a torque converter automatic because the torque converter allows the engine to “free wheel” a bit. They also like to upshift pretty quickly so engine braking in a 6th gear basically does nothing. Even locking it to first or second isn’t quite the same as in a manual. Also I think some automatics will put the car in neutral sometimes when coasting. I think my Mazda 3 does this. You can definitely feel a small jolt when you are cruising down a hill on the highway and switch to “manual” mode as is it tries to engage 6th gear.
Oh, and as a side note, my new car with an automatic transmission and a 400+ HP engine accelerates from zero to 60 faster and smoother than any one of my previous cars.
Yes, automatic transmissions have a big advantage in acceleration which is why they're so common in drag racing. The torque converter means there's an "extra low gear" to provide more torque from a standstill, and there's no need to operate a clutch that can take repeated slipping without quickly wearing out --- cars can "slip" the torque converter at full throttle for a moment and launch with the engine already running near the optimal RPM for peak power.
In fact, one of the most popular transmissions in drag racing is a two-speed automatic from the early 50s:
I've never really seen the issue with "manual in traffic" -- there's almost always a gear or two that allow you to go a the speed of traffic without tons of shifting. Stop and go? 2nd probably goes from "creep" to "moderate speed"
Anyhow, electric cars are better all around -- at least those with "one pedal driving" where the speed pedal goes all the way to zero or nearly zero.
My dislike of automatics is the indeterminate lag between request for a particular speed and when the car decides to shift to the appropriate gear to get to that speed as quickly as I've indicated I want to get there. Plus with ICE cars there's all sorts of other tedious inertia to contend with around engine RPM and turbo spool state and such. At least a manual provides better determinism around throttle behavior.
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