hammered hell

[olerodder]

Duckbilled Platypus?

Now that's funny!

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[DrZed]

It's not even automatic: It just doesn't shift gears. Like most electric vehicles, it has a reduction gear with a fixed ratio.
Good news: If you own a Mach-E you can tell your gearhead buddies it has a 9.05 rear end.
It can go over 100mph because it can spin the motor(s) over 13,000rpm.
It's geared short for city driving, and that also serves the ever-important 0-60 test.

If you take it on the highway, it will probably lose efficiency due to spinning the motor so fast, just like any other EV.

People who drank the Tesla cool-aid carry on about how the motor has such a broad RPM range it doesn't need to shift gears. Tesla doesn't like everyone to know that they did see an advantage to shifting gears, tried to develop a 2-speed automatic for their cars, and failed. They failed at it, so they resumed the story that they don't need it. Their travel range is great at 35mph and 4000rpm, terrible at 75mph at 8,700rpm or whatever it is.

Porsche also saw an advantage to shifting gears, and their EV has a 2-speed transmission. I think Tesla said "You can't make a viable transmission for something with this much torque" and Porsche engineers were like "Hold mein bier".

Where many EVs are tiny things with ruthlessly utilitarian amounts of power, and the Tesla and Porsche EVs are mostly novelties for rich people, the Mach-E is somewhere in between.
I don't mind that it shares styling cues with the Mustang, though I also want to know how drunk the committee had to be to put the Mustang name on it.
I also don't understand why it needs so much ground clearance - Is someone going to drive it in snow when anybody who knows anything knows weather that cold is bad for batteries?
And why the **** did it have to have "electronically controlled" door handles? Hasn't the world figured out that Tesla's electric door handles are the least reliable part of their car?

I'm appreciating you and this response. Want to now read more of your posts.

 

[Hack]

Porsche also saw an advantage to shifting gears, and their EV has a 2-speed transmission. I think Tesla said "You can't make a viable transmission for something with this much torque" and Porsche engineers were like "Hold mein bier".

Gear Vendors has something that handles lots of torque. They advertise 1200+ HP. Proven, simple technology that's been around for years. My assumption would be that Tesla has other reasons that they aren't talking about for not adding an overdrive ($$).

Yes I agree with your implication that Porsche engineers are very capable, but there's nothing necessarily cutting edge about a transmission that can handle mega torque.

 

[Rapid Red]

Duckbilled Platypus?

Full size slot car ...

 

[ShadesOfBloo]

Gear Vendors has something that handles lots of torque. They advertise 1200+ HP. Proven, simple technology that's been around for years. My assumption would be that Tesla has other reasons that they aren't talking about for not adding an overdrive ($$).

Yes I agree with your implication that Porsche engineers are very capable, but there's nothing necessarily cutting edge about a transmission that can handle mega torque.

No, there's nothing cutting edge about it.
Quite a few WW2 fighter planes had 2-speed transmissions (some automatic, some manual) to change gears for their superchargers. A P-51D Mustang (one of the automatic ones) had about 1400hp and must have used a lot of torque just for the 3-stage supercharger.
And since it's a WWII fighter plane with a Merlin engine, that really means design work started in the 1930s.

It's just Tesla that threw their hands up and said "F it".

ZF says they're working on a 2-speed transmission for EVs, and it should give most EVs a 5% increase in range. If a manufacturer is interested, they'll have to design a vehicle with room for the transmission. And do some calculation like checking that the (design work/number of vehicles) + transmission price is less than 5% of total vehicle cost. Or (just as likely) devise an ad campaign to convince the customers it's worth the cost.

Tesla decided to increase range by working on battery technology instead. ...And make sure their "autopilot" feature gets more attention than their attempt at a gear-changing transmission.

 

[Norm Peterson]

I'm sure that at some point off in the future, EVs are going to come under pressure to increase their MPGe's. Somebody's going to figure out that even EVs will need to be yet more efficient in terms of battery power usage . . . can't just keep on going to bigger battery packs.

My take is that somewhat less powerful motors may bring on more reason to offer multi-speed transmissions for them. Maybe not 5 or 6 or 8 or 10 speed, but I can picture at least two and likely three. I guess that'd then mean blocking access to the taller gears for reversing, assuming that reverse is still accomplished by reversing the motor rotation.


Norm

 

[Hack]

I'm sure that at some point off in the future, EVs are going to come under pressure to increase their MPGe's. Somebody's going to figure out that even EVs will need to be yet more efficient in terms of battery power usage . . . can't just keep on going to bigger battery packs.

My take is that somewhat less powerful motors may bring on more reason to offer multi-speed transmissions for them. Maybe not 5 or 6 or 8 or 10 speed, but I can picture at least two and likely three. I guess that'd then mean blocking access to the taller gears for reversing, assuming that reverse is still accomplished by reversing the motor rotation.


Norm

Right, bigger batteries are fine and all, but they take a really long time to recharge. Even if the charging time issue gets solved, it's expensive to have your EV use all that energy. Just like driving a gas guzzling ICE vehicle.

 

[ShadesOfBloo]

...Maybe not 5 or 6 or 8 or 10 speed, but I can picture at least two and likely three. I guess that'd then mean blocking access to the taller gears for reversing, assuming that reverse is still accomplished by reversing the motor rotation.

Norm

I was thinking I could like an EV if it came with a 3-speed manual transmission.

Even electric motors have an RPM range where their efficiency is optimized, and in most cases it's pretty low compared to the maximum RPM it can spin.

Most EVs are committed to a single gear ratio, and they tend to pick a ratio for city driving. If you take it to a 75mph zone, the energy efficiency suffers.
If you take it to a 1/4 mi drag strip, you're leaving something on the table because as you rev the motor WAY past its efficient RPM range, the power drops. A Tesla loses 1/4 to 1/2 of its power by the end of a quarter-mile drag strip, and that's why they keep trying to do their drag racing publicity stunts in shorter lengths (often unspecified lengths).
E.g.: When they bragged "We beat LaFerrari in a 200m race!" that's 1/8th of a mile.
If you take a car to a road course, and it's geared for 0-60 runs, you're leaving even more on the table.

So for highway driving and the occasional track day I want at least 2 gears, probably 3.
1st gear is for city driving.
2nd gear puts the motor at the optimum RPM for efficiency at 55mph.
3rd gear gives it optimum RPM at 75mph.

And how does the transmission know when to shift? It doesn't! Leave that to the driver, and save lots of money on software development.

In an electric car, a manual transmission would give me the option to shift, but would still be usable to friends and family who are "manually disinclined". You wouldn't need the clutch to get going. If you're parked in your driveway or stopped at a light you can leave it in gear, because an electric motor doesn't need to idle. Just give it current when you want to start moving.

A noob who's afraid to shift while moving can put it in 2nd gear in the driveway, and then proceed to the highway.

I can go to a road course and, because there's such a thing as "3rd gear", top speed would now be limited by air drag rather than the maximum RPM of the motor.

...And anyone who knows old-school musclecars firsthand will hear "3-speed" and be like "What is this, the '60s?!?"

 

[ShadesOfBloo]

For that proposed manual-transmission EV, I think good tachometer markings would be important.

I envision a green mark at the RPM where the motor gets its best energy efficiency. It can be a line, or a range, depending on the motor.
A yellow mark to suggest a shift point, and
a red mark that means "Seriously, you should have shifted by now!"

If we use a Tesla motor as an example, we probably put the green mark at 4000rpm.
Yellow mark at 10,000 rpm to remind you the power is all in, and you should think about shifting.
Red line at 12,000 rpm because, OMG you're due to shift now.

Don't bother marking all 16,500rpm on the tachometer. The last 3000rpm aren't useful, and you're just forcing smaller and smaller font.

 

[Norm Peterson]

Don't bother marking all 16,500rpm on the tachometer. The last 3000rpm aren't useful, and you're just forcing smaller and smaller font'

Or you could compress the scale of that last 3000 rpm down to fit into the same arc that would display 1000 rpm elsewhere and let the electronics deal with slowing down the indicator.


Norm

 

[SpeedLu]

Yea it's a piece of shit, we know.

 

[olerodder]

The Mustang Cobra Jet 1400 is an EV with 1400hp, does the 1/4 mile in sub 8 seconds at over 170MPH. That's not bad for an EV!

 

[Roman]

When I saw one in person I was surprised at how small it was. Our Edge felt big in comparison.

 

[ShadesOfBloo]

I was thinking I could like an EV if it came with a 3-speed manual transmission.

Even electric motors have an RPM range where their efficiency is optimized, and in most cases it's pretty low compared to the maximum RPM it can spin.

Most EVs are committed to a single gear ratio, and they tend to pick a ratio for city driving. If you take it to a 75mph zone, the energy efficiency suffers.
If you take it to a 1/4 mi drag strip, you're leaving something on the table because as you rev the motor WAY past its efficient RPM range, the power drops. A Tesla loses 1/4 to 1/2 of its power by the end of a quarter-mile drag strip, and that's why they keep trying to do their drag racing publicity stunts in shorter lengths (often unspecified lengths).
E.g.: When they bragged "We beat LaFerrari in a 200m race!" that's 1/8th of a mile.
If you take a car to a road course, and it's geared for 0-60 runs, you're leaving even more on the table.

Someone else thought a 3-speed transmission was good for an EV:
https://carbuzz.com/news/electric-cars-are-perfect-for-3-speed-gearboxes-says-zf

https://newatlas.com/antonov-3-speed-transmission-ev/19088/

Now, I just want to get through to them that they can save a lot on software and electronics if they make my transmission manual.

 

[Oakley]

The Mustang Cobra Jet 1400 is an EV with 1400hp, does the 1/4 mile in sub 8 seconds at over 170MPH. That's not bad for an EV!

this is like using AI to generate art and then pretending like its awesome.

kinda, but it misses the point and always falls short.

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