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by adrianN 3321 days ago
I doubt that there are many drivers who can outperform a modern automatic transmission.
2 comments

I disagree. As eeks points out, fully automatic transmissions are kind of awful at making decisions.

I have a case when I was driving into work this morning. I got stuck behind a funeral procession going 35 MPH on a 65 MPH interstate highway (Uggghhhhh)

I look to my left-mirror, and I see a spot I can feasibly make, I just gotta time it right to get "into" the flow of traffic. So what do I do?

I drop to 2nd gear (The Gear ratios on the Ford Focus are kinda "weak"). My engine roars but its cool, because my engine's top-Torque is in the 4000RPM to 6000RPM band. When the "spot" opens up, I floor the acceleration pedal and get in just fine.

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A fully automatic vehicle wouldn't "know" that I wanted to "prepare" for the sudden acceleration. It only knows after you push the pedal.

A manual driver however, can tell the car to "prepare" for acceleration, so that when you push the accelerator you are 100% ready to go.

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Semi-automatic vehicles (including some "sport" CVT engines I've test-driven) would work. The important bit is to be able to change gears way ahead of time BEFORE you push the accelerator.

Automatic transmissions are better & smarter than you. you may have to drive a little differently if you're driving an automatic in the scenario you described, but saying that it doesn't ''know'' what you wanted to do means either your transmission is virgin & hasn't learned your habits, or, had a different driver for several years & is shifting at the wrong points. This 'ready to go' thing is all hogwash manual elitism.
Look, a CVT semi-automatic probably would outperform me. I'm no master driver or whatever.

But a typical automatic transmission? Dude, I have a huge advantage as a human. I have eyes. I can see things the engine cannot.

It takes time for a internal combustion engine to rev up to its ideal torque band. The Ford Focus is a turbocharged engine, which means it only achieves maximum torque above 4000 RPM.

Since most automatic transmissions are tuned for fuel efficiency (ie: 2000RPM band or so), they will perform worse when you're trying to accelerate. The manual driver has the advantage that they can choose fuel efficiency (ie: 2000RPM most of the time), or in cases of emergency... kick it into (low) gear for very high RPM to maximize the torque band.

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ICE Engines are all about tradeoffs, and the manual driver can choose the RPM-band that best matches the situation.

Would a properly tuned automatic beat me in fuel economy? Probably.

Would a properly tuned automatic beat me in acceleration? Probably.

But no automtaic can be tuned to do both at the same time. Since high-Torque is high-RPM only... and fuel efficiency is low-RPM only... the computer cannot be tuned to try to do both at the same time.

Unless it's hooked into a sophisticated camera system, how could an automatic transmission possibly learn that I'm going to want a lot of acceleration in a couple of seconds once this car passes me?

By the way, I'm not a manual elitist, but rather an EV elitist. I like not having a transmission at all.

Automatic, yes. Semi-automatic, no. With semi, the driver makes the decision, and the system execute it (the best in class is within 10ms IIRC).