GM Getting into the EV Conversion Business?
 

GM electric crate motor, anyone?
https://youtu.be/ilZ_fb75j_8

An electric motor that bolts up to a GM transmission would solve a problem of problems.
The T-10 4 speed manual would be more than enough gears.

With peak torque from 1-9000 rpm, you would use only one or two of those four gears.

Well I can't recall any 2 or 3 speed manuals.
Now I have heard rumors of torque converterless 2 speed powerglide transmissions set up for electric drag racing.

I think you'd have to go back to the 1960s and "three on the tree". Though this link says you could find them on trucks up until the '80s: https://autoweek.com/article/classic...nuals-1986-yes

I can, but they were on antiques

My dad had an old car with 3 on the tree

Model T’s had a “three” speed
2 forward and
1 reverse

The torque falls off as the motor gains RPM. All electric motors have peak torque at stall. A continuously variable transmission, keeping the motor near stall with acceleration, would give the best acceleration.

I don't think a 3 on the tree was ever made that can handle that torque.
A 4 on the floor T-10 should be able to handle that torque if it's a high dollar one.

Using a tranny is a good idea if you're using a low-powered or marginally-powered motor.

I've driven conversions that use the stock five speed on economy cars. You start in 2nd or 3rd, but you still have 1st for climbing hills and steep ramps.

Not a bad way to do it.

That's a good point. Well, some engines used in conversions may eventually not be meant to be directly reversible, and then a transmission becomes a must. I don't remember when it was done, but someone converted an Opel Astra to electric here in Brazil with a 20hp engine and claimed to have retained the transmission mostly because the engine wouldn't operate properly on reverse...

That's interesting.

I wonder how much you can save, in terms of electricity, going for a smaller motor? Looking at charts, it seems like EV kwh use varies more by weight than power or performance.

Possibly most of the savings are in upfront costs and weight and packaging penalties.

Not true if you control peak current electronically like all EVs do. With a motor controller capping peak amps at, say, 450A (in my Electric Booger), torque remains constant from zero rpm up to the rpm where the amount of voltage required to maintain said current is equal to pack voltage. In the Electric Booger this is 4000 rpm and 68V (pack voltage sag @ high current). Electric motor current is proportional to torque.

An AC motor's huge advantage is lack of back EMF, so voltage required to maintain a set current does not rise with rpm, which allows for a massive rpm range. If you look at the torque curve on many available AC motor kits, they are flat from nearly zero to very high rpm.

Well, that engine was not too big, but IIRC it was quite low-revving.

The smaller motor does weigh a bit less. IMHO it is more important that it fits into a smaller space.

The motor will have a certain rating for 1 hour or 2 hour use ... likely what I'd use for a conversion ... the continuous rating would be lower. But the extra torque for accelerating would be less, so running through the gears may make it more fun to drive.

An 1800 rpm, 4 pole, AC induction motor used in industry has a minimum current ... just spinning with no load .. around 1/3 amps. I have not measured .. or read about .. any similar minimum current on AC motors used in cars. ASS U MING (not a good idea) that there is a similar minimum, there may be a marginal advantage to using a smaller motor. It might be hard to separate the contributions of lower weight from lower max rated current in real-world testing ...

Not so fast, GM!
 

At least not if Trump has his way:
https://twitter.com/realDonaldTrump/...gm-layoff-plan

A subtle nudge by the POTUS, as ever.
Little chance the Congress lets him have it, but GM be warned.

I appreciate that you posted the full quote. The media (at least CNN that I saw) doesn't do a good job of that, so you miss a lot of context.

conversion motors and GM's EV subsidies
 

More context is a good thing on Trump's bluster, as GM is only 10,000 cars away from their 200,000 vehicle cap on EV tax credits anyway. The credit will go from $7500 to $3750 for the 2nd quarter after hitting that target, then down to $1875 for another 3 months before hitting zero.
https://www.edmunds.com/fuel-economy...x-credits.html There are efforts afoot to extend that credit, which is the main thing he could affect.

Now back to motors for conversions. Analogous to rotor tip speed with helicopters, the speed of the commutator under the brushes is a limiting factor on series wound brushed motors, which is proportional to the motor diameter. So a larger motor will have more starting torque, but a lower top RPM. Since starting torque is rarely an issue in EV conversions but highway passing power is, a smaller motor, or especially multiple small motors can be the best solution, as they can reach higher RPMs. Efficiency will not change appreciably between say a 6" and a 9" series motor.

My 9" series motor has externally wired fields that can be switched from series to parallel. This provides maximum starting torque in series, and then further down the dragstrip, switching to parallel provides more power at high RPMs.

And if I understand correctly, it's not GM that gets the tax credit, it's the person who buys the EV.

GM gets to charge more for the car, helping make it profitable, while the customer pays the same price with the taxpayer eating the difference.

You're technically correct, but practically speaking, that credit goes into GM's income.

Actually, the rpm limit on my kostov is due to the windings not being restricted. Similar to most +13 inch series motors. The comm flies apart next.

The fix is kevlar banding, but at only a 1000 or so more rpm. Back EMF @ 6000 rpm kinda sucks big time, too

Hello all,

Cool idea/concept! Having to watch video to get the relevant information is annoying, though, so I poked around. If you search on "eCOPO Camaro" you'll get a bunch of articles.

Here's a decent one.

The upshot is two Borg-Warner HVH 250-150 motors plus a controller in a package that is a bolt-in replacement for a GM LS-series smallblock.

Note that Remy and Borg-Warner use suspiciously similar model numbers for their motors, they are likely the same motors.

Batteries are in 175-lb 200V modules, the demonstrator is running 4 modules for 32kwh at 800V.

I wonder how much tweaking they plan on doing in terms of trying to mimic an engine's power-band, so that using all the gears in the transmission makes sense, and you don't need to run a ridiculous final drive ratio.

I'd like to see this "crate motor" repackaged to mimic a *transmission* rather than an engine, and have it be single-speed. Offer RWD and 4x4 tailshaft/tailhousing versions, to offer a driveshaft mount or transfercase mount. Mimic a common GM transmission. The motors themselves are small, and GM has already squeezed them into a 4L80e case before - see the older GM Two-Mode Hybrid system 2ML70 transmission that incorporated two HVH 250 Remy motors, in a package that is a drop-in replacement for a 4L80e transmission.

With planetary reduction gears (again, set up to not require a ridiculous final drive ratio) and no need for shifting and associated clutches, etc, it should make for a very slim design. Standard fittings for external transmission cooler lines, too. Since most transmissions only have the one rear mount, it'll need some sort of front "cradle" structure to link up to the motor mounts. With the right design, they could easily offer multiple variations cheaply, designed to drop in for anything from a small-block/Powerglide up through a big-block/10R90 combo. Different power outputs can potentially be obtained with different numbers of motors. The front mounting "cradle" can hold the controller, too. They can either integrate a cooling package on that same cradle, and have the installer provide ducting, or leave it up to the installer to choose an approprate radiator/cooler combo to put in the traditional location. A standard V6 radiator with integrated trans cooler would probably be overkill, given how efficient these motors and controllers are.

Similar idea could be done to do a drop-in FWD unit that replaces a transaxle/engine assembly, though it will have the final drive in it as well, and there's a lot less "standardization" in that market, so probably not very attractive from a market size standpoint.

Sure wish I had a lump of working capital, a cheaper cost of living, and a better head for business...

I want one. ^^^^^^^ drool, drool.

Don't we all. :):rolleyes:

That would allow either a good amount of batteries, or a built-in range extender for those who are still concerned about range-anxiety.

A single-speed drivetrain needs double the horsepower rating and fat wires to carry the current at start. Toyota uses buried magnets in their AC motor to reduce the drop in torque at higher RPMs.

Here a two-speed planetary box, but it's $4K.

EVTV Motor Verks Store: Torque Box 2:1 Gear Box, Drive Train Components, torquebox

And people trying to roll their own from GM parts;

https://www.diyelectriccar.com/forum...ar-180777.html

Jaguar Land Rover is already converting owner's XKEs to electric:

https://duckduckgo.com/?q=Jaguar+XKE...on&t=h_&ia=web

Hmmm a powerslide low pack in a fancy expensive case. Typical EVTV.

DIYELECTRIC is possibly dying due to new owners or lack of interest. Whole lot of new know-it-alls that are rather dumb, too.

EVTV have declared victory, nobody needs to make their own EV anymore, you just buy one. And even if you want to, there're OEM components at 1/10th the price.

They offer that $4K box, but I doubt they moved many of them.

They've gone into solar storage solutions.

edit:
Aston Martin is going resto-mod:

theverge.com:Aston Martin will make old cars electric so they don’t get banned from cities

GM is causing business conversion to EV
 

... in a way. If Musk gets to do what he says the's thinking about:
https://electrek.co/2018/12/07/tesla...ies-elon-musk/