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Comment by coryrc | Hacker News Reader

Wildly ignorant choice. No one's going to sell a big enough battery without at least modeling its effect on crashworthiness, which is expensive. No, you can't run the car without the engine running; you won't have oil flow in the transmission, power steering, or power brakes. The car will handle like shit with so much unsprung weight (which is why no commercial car has ever used them, just demos). And the price quoted is basically COGS!

Nobody on this process must have ever been involved in DFM.

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> No, you can't run the car without the engine running; you won't have oil flow in the transmission, power steering, or power brakes

You might have missed some key points in the pitch. Slide 4 has e-hydraulics for steering and braking.

They're just clip-art on a slide.

It's not possible for a reasonable price. NRE costs per model would be high, making a farce of "Make your car electric for 5k".

For the mechanic installing the device, you have to have an installation manual listing where every cable and hose needs to go and be secured. And you need to choose well, because if it rubs anywhere: recall and fix (is there enough money in $5k for recalls? No).

You have to hack the ECM, /per model/, to allow you to drive without the engine actually running.

It's preposterous.

That doesn't solve lack of lubrication to the transmission. Go read your owner's manual under the section regarding towing. There are almost always restrictions on maximum speed and distance with the drive wheels not lifted.

As the other commenter pointed out, there's a lot of hand-waiving going on by the kid who won the contest; it's like the farside comic where there's a giant "magic happens" in the middle of a board full of mathematic scribbling.

For example: running HVDC to the engine compartment (for the AC, power steering, and vacuum pump) from the spare tire well in a vehicle whose undercarriage isn't designed for it requires pretty substantial armoring.

The other problem: in-wheel motors are not new (Mistubishi sunk a LOT of R&D into it), and they haven't taken off for a reason.

They massively increase unsprung weight. Your average car wheel weighs maybe 30-40lb at most. He's probably doubling that. That means atrocious ride quality and traction issues, because the tire's going to be bouncing around like crazy due to the suspension not being designed to dampen that much weight.

The motor is also subject to all the vibration normally soaked by the suspension and vehicle frame. Trying to get an electric motor to withstand that sort of vibration is not a trivial problem.

This is just a bunch of hogwash from Dyson. The kid figured out that what they care about is a nice big fat PR grabber, and he gave them one.

My reading was the the motors selectively decouple the wheels from the drive train, in which case the transmission would be inactive.

Transmissions have their own, independant, lubrication system. It's driven off the input power from the engine.

Right, and it's proposed the engine wouldn't be running.

You don’t need a transmission if you have hub motors. It’ll be sat on the garage floor, so it would be a great surprise if it was running.

I’m planning on doing something similar on my old hilux. The lack of power steering or power breaks or any auxiliary system that relies on the engine simplifies the build substantially.

His supposed kit converts a car into a hybrid, not a pure electric vehicle. You still need the original drivetrain.

> REVR is a retrofit kit that incorporates all systems required for the conversion of a light ICE vehicle to hybrid electric.

laughably, transparently poor implementation.

While using the gasoline engine, the power accessories (power steering, power brake assist, ABS!) are functional, but when the gas engine is powered off, you'll have none of them? That's going to get someone killed. And on top of that, the climate control issues -- A/C won't work, and the heat will only last so long as the gas engine is preheated and then only briefly as the coolant isn't being circulated.

The concept of hybrid is an invisible marriage of gas/electric propulsion brought to us by Toyota who perfected it in the Prius. This is just a hack as far as I am concerned. I would be more impressed if the engine were removed entirely, and this motor were bolted up to the transmission as a replacement flywheel.

Just have it run in addition to the engine.

You still reduce fuel use, don't need to change any other parts to work without the engine.

You just basically need to know when the accelerator and break (and perhaps clutch?) Were pressed, and perhaps change accelerator response to make it feel more natural.

I'm totally ignorant on this subject, but what if you just had the vehicle engine on and idling the whole time you were driving? That way it could power the climate control, power steering, etc., but presumably use much, much less fuel than if you were using it to accelerate.

Sure, then call it hybrid assist. Gasoline engines are most inefficient at small loads though, so you aren't saving as much as you think.

The price of a used Leaf in the USA can be $3000: https://seattle.craigslist.org/sno/ctd/d/everett-2013-nissan...

So if you just want an EV, you can get a whole working car, with more range, for less.

I actually looked for a used Leaf for just this reason. Ended up getting a CMAX PHEV, which has suited my needs quite nicely for the last 5 years.

I'm just hopeful that there is some way to retrofit the millions of existing ICE vehicles out there in a way that's cost-effective.

The millions of existing ICE vehicles can be retained by the people who own cars but use them rarely, and new EVs can be used by people who need to drive significant distances.

In the US you might be able to, but this guy is Australian and the cheapest leaf I can find here is just shy of $12k.

That's always been my thought as well. Why can't I just have some rechargeable component that significantly boosts my gas mileage for the typical 30-40 mile daily drive. The occasional 200-300 mile long distance trip I'm fine with using gas purely.

Because would you really spend $10k+ to do that?

No, you'd buy a Prius instead, because it'd work better and be cheaper.

I would certainly consider it for 10k. Because no I wouldn't buy a Prius because they look goofy and I like my current vehicle. 10k is close to the tipping point, but would probably be worth it. If it was cheaper though definitely.

It’s also pushing in the hub in a way it is t designed to be pushed on…

Despite the title, this article is actually about creating a hybrid so the engine will always be running.

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