[MattsAwesomeStuff]

Local junkyard accidentally picked up a 2012 Prius V. They never buy hybrids.

I'm wondering what I should yank from it. Open to advice.

I went today to look at it...

- To my shock, while the 12v battery was removed, the HV hybrid battery was still in there. The safety disconnect wasn't even deactivated. Eep! I later confirmed that they're not supposed to do hybrids, their price list doesn't even have hybrid parts on it.

- After a bit of back and forth to the yard, and the owner on the phone, they sold me the 202v battery as "a battery" ($33), so, now I at least have some smaller contactors and fuses and such too. They also sold me the inverter as an ECM ($50). I didn't have time to grab cables, hoses, reservoir or pump, so, I'll back tomorrow to try to yank those out.

Battery seems to be in good shape. I'm pretty happy to have it, they sell for $800 around here. While it's 80lbs and only 1.3kWh, it's 202v and 125A. So, instead of having to have my battery pack design finalized before testing, or building a test pack, this is a convenient test platform that'll give me ~5 miles at highway speed. Enough to get to the inspection shop and such when the time comes, to get me road-legal and street-parkable while I continue work on it.

Contactors:

And the Gen 3 Inverter:

...

That leaves the steering column (for sure the easiest ones to use are Prius) and the throttle pedal (just because I don't know what would have a nicer throttle pedal, I'm open to suggestions of other electronic pedals that would be more suitable in a sports car).

...

To recap my use case:

I have a 1970 Opel GT (small sports car).

I'm using a forklift motor, and so far, a Prius Gen 2 inverter that I might just give up on.

If it makes sense, I would grab the air conditioner from the Prius tomorrow too. Only because it's motor-controlled, (and the Gen 2 inverter already has a built-in inverter for it), not engine-driven. But if anyone has advice on that I'm interested. Should I only grab the motor/pump? Would it be foolish to buy the lines and the evaporator and condenser?

Anyone have any advice on what else I might want to snag while I'm there? I'm not likely to find another Prius in a self-serve lot for a couple years.

 

[remy_martian]

Maybe grab the brake booster, ya lucky weasel 😂

 

[MattsAwesomeStuff]

Maybe grab the brake booster, ya lucky weasel 😂

Interesting, I hadn't heard about that. Looks like there's no pancake booster thingy, seems fairly compact.

I was considering the mechanical booster that's on teslas and a few others (it's a bosch unit I think).

I don't know enough about it yet to know if I want it. Looks like there's a control module on it which presumably has to be spoofed.

Seen anyone repurpose these yet?

 

[remy_martian]

No idea. I'm happy with an old school vacuum pump on my projects lineup.

With the rate at which this hobby is ramping, it may just be a matter of time if it hasn't been repurposed already. God bless $6/gallon gas, lol

 

[reiderM]

That leaves the steering column (for sure the easiest ones to use are Prius) and the throttle pedal (just because I don't know what would have a nicer throttle pedal, I'm open to suggestions of other electronic pedals that would be more suitable in a sports car).

Depends if you want floor mount or wall mount. Prius pedal is a good option for wall mount.

 

[remy_martian]

There's not much floor area in the baby German Corvette...

 

[brian_]

Interesting, I hadn't heard about that. Looks like there's no pancake booster thingy, seems fairly compact.

Right - no vacuum assist unit.

I was considering the mechanical booster that's on teslas and a few others (it's a bosch unit I think).

The one used by Tesla (and many other companies, for EV, hybrid, and ICE applications) is the Bosch iBooster. I don't know what Toyota uses.

I don't know enough about it yet to know if I want it. Looks like there's a control module on it which presumably has to be spoofed.

Seen anyone repurpose these yet?

Yes, it has a control unit, but if it's the Bosch you don't need to do anything sophisticated to trick it, at least for basic functionality. If you want the friction brakes to back off in coordination with regenerative braking, you'll need more - Bosch sells an additional electronic module to do that, but although this functionality is normal for even the cheapest EV or hybrid, conversions in general don't have it.

Yes, lots of the Bosch units have been adapted to different vehicles, typically for EV conversions. Here's SuperfastMatt's take:
Inside Tesla's Brake Booster (And How To Use It On Any Car)

 

[MattsAwesomeStuff]

There's not much floor area in the baby German Corvette...

Indeed.

Original is wall-mount...

So, the Prius's wall-mount seems to be the way to go. Quite hassel-free once you crawl all the way in there, just 2 bolts.

Yes, lots of the Bosch units have been adapted to different vehicles, typically for EV conversions.

Sorry, I phrased that poorly. What I meant was, I was fairly well researched on the Bosch unit and that was my plan, but, was asking Remy/anyone if the Prius booster had been reverse engineered yet, since, the Bosch ones are too new to appear in scrap yards yet, and thus will cost me a few hundred dollars. Good news, at my current rate of progress, I'm sure they'll be in the junkyards before I'm needing brakes anyways.

...

Went back and grabbed the steering column (didn't have time to strip the steering wheel off, so they charged me for it). $60 for the column. $65 for the wheel and airbag. They said they didn't care about the indicators, which, is nice if I wanted to use them, and hadn't beat and cut the wiring off them to get it out.

For those that don't know, Prius power steering is directly electric, and it only needs 12v. If it can't communicate with the main computer, (it won't, it's gone) it defaults to the steering assist you'd get at 43mph. No other wheel speed sensory trickery necessary. Just 12v.

...

Grabbed a $7 reservoir and the inverter coolant pump while I was at it, since the place I bought my Gen 2 inverter from removed it before they sold it to me.

...

Now the air compressor... well, here's the connection to the inverter:

... I note that there are only 2 conductors. So, seems like on the Gen 3 Prius, there's presumably just battery voltage headed to the compressor and some signal wires. So, perhaps there's an inverter module on the compressor itself? Ugh.

On the Gen 2, the A/C inverter is internal to the main inverter case, and your 3 phase wires to out to the compressor. Probably makes it a lot worse for electrical noise, but it's one less thing to engineer.

I'm probably going to skip it.

Damien suggested I should probably grab the transaxle and axles, but I'm resisting the temptation to do an AWD so I don't think I will.

I got one set of motors wires off, and 90% of the HV harness, so, will probably go back a third time to try to grab the rest of that.

 

[brian_]

What I meant was, I was fairly well researched on the Bosch unit and that was my plan, but, was asking Remy/anyone if the Prius booster had been reverse engineered yet, since, the Bosch ones are too new to appear in scrap yards yet, and thus will cost me a few hundred dollars

The iBooster is nine years old, but if by "in scrap yards" you mean "in U-pick yards", they wouldn't likely be there... and might not be common in those places before many of us die of old age.

 

[MattsAwesomeStuff]

The iBooster is nine years old, but if by "in scrap yards" you mean "in U-pick yards", they wouldn't likely be there... and might not be common in those places before many of us die of old age.

Well, 2018 or newer Honda Accords. Otherwise I'm buying Tesla parts, and, that's too rich for me.

 

[brian_]

Well, 2018 or newer Honda Accords. Otherwise I'm buying Tesla parts, and, that's too rich for me.

I don't know when each model started using the iBooster, but there are few other than Tesla that started with the first generation unit, as listed by EVcreate in iBooster donor vehicles. The Malibu, for instance, used the iBooster (in at least some variants) at least as early as 2016. I'm not suggesting that these things are common or cheap in salvage, only that it's not just Tesla, Accord, or nothing.

 

[reiderM]

... I note that there are only 2 conductors. So, seems like on the Gen 3 Prius, there's presumably just battery voltage headed to the compressor and some signal wires. So, perhaps there's an inverter module on the compressor itself? Ugh.

I don't think this is necessarily an issue, often the controls for these compressors are just a simple PWM signal. Otherwise probably CANbus, are the comms wires twisted pair/shielded?

 

[remy_martian]

The early ones are PWM. The later ones are CAN. What that means for Priuses, I have no idea.

 

[MattsAwesomeStuff]

I don't think this is necessarily an issue, often the controls for these compressors are just a simple PWM signal.

Also, this may be stupid and obvious, but, it only occurred to me a day later that, it doesn't matter if it has its own inverter, if it has a 3phase motor, at some point in there, there are 3 wires I can connect to my Gen 2. Going the other way, from a Gen 3 controller to using a Gen 2 compressor, you'd be missing an inverter.

Otherwise probably CANbus, are the comms wires twisted pair/shielded?

No shielded pair I don't think, I grabbed the wire stub but not very carefully, snipped it out of most of the harness. Every day I've been there (day 3 now), they've been pulling cars out of that row, so I've been treating it as "might not be here tomorrow", and cut what I had to, to get it out.

Also, whatever it has for an inverter is... not large. There was no module, just a few control wires and the bat- bat+ wires. Maybe the size of a deck of cars, or less.

I found it interesting that the coolant flows right through the motor. Right inside the A/C port you can see windings with nothing separating them.

I don't know how standardized A/C fittings are, whether they're unique to the model, common to a brand, or almost global to any vehicle. I grabbed the two aluminum lines that connected directly to the compressor. I didn't get the condenser or evaporator (yet?). Again, I don't know how standardized this is. The condenser was as large as the rad, which seemed too big for my car. Ideally once I have things Tetrised later in the build, I could choose "any" small condenser that fits the space, accept the cooling tradeoff for the reduced size, but otherwise have everything work fine. Is that an option?

... also...

I know what refridgerant tastes like. It should have occurred to me that if they skipped the yard prep in terms of the battery, they also skipped the yard prep in terms of safely draining the refridgerant. Loosened one line off slowly and listened for the hissing. Nothing happened. Took one line off and got soaked with it, including a mouthful. Blech.

...

Nabbed the long HVDC battery wires and the 12v+ wire. Probably too weak to use on the final car, but if nothing else I'll shove thicker wires into the orange loom later.

 

[remy_martian]

You're gunna get Big Brother hippies in dark suits and sunglasses knocking on your door for that freon release:

China confirmed as source of rise in CFCs - BBC News

Atmospheric observations pinpoint eastern China as the source of a rise in ozone-destroying chemicals.

www.bbc.com

Your twisted pair insight is a brilliant way to deduce pwm...your next assignment at The Yard is to find non-twisted pair, pwm, EPS racks 🤓

 

[brian_]

I found it interesting that the coolant flows right through the motor. Right inside the A/C port you can see windings with nothing separating them.

I believe that's normal for electrically powered refrigeration systems. The compressor and motor are entirely within the sealed volume, so there is no need for shaft seals (an advantage over an external drive such as a belt from an engine) and the refrigerant can cool the motor. Any common refrigerant is non-conductive, so there's no problem immersing the motor in it.

I know what refridgerant tastes like. It should have occurred to me that if they skipped the yard prep in terms of the battery, they also skipped the yard prep in terms of safely draining the refridgerant. Loosened one line off slowly and listened for the hissing. Nothing happened. Took one line off and got soaked with it, including a mouthful. Blech.

That's bad, but not as bad as it would have been in the chlorofluorocarbon (CFC, e.g. R12) days. More recent refrigerants (hydrofluorocarbons or HFCs such as R134a, and now hydrofluoroolefins - HFO - such as R-1234yf) are not particularly toxic (R134a is even used in small quantities medically), and they're much less harmful environmentally (which is why R12 is banned).

Any refrigerant for this sort of system will be vapour at ambient temperature (since you were not doing this at -30 C); unless there was something such as a check valve or closed port of the compressor blocking the fluid path to keep the refrigerant under pressure, it wouldn't be liquid; even the liquid would flash to vapour quickly, with the associated chilling effect. Did you get a mouthful of lubricant (NipponDenso 11 compressor oil), rather than refrigerant?

 

[MattsAwesomeStuff]

Your twisted pair insight is a brilliant way to deduce pwm...your next assignment at The Yard is to find non-twisted pair, pwm, EPS racks 🤓

Reider's idea, not mine.

I'm done searching, I have the minimum set of things I need. I'm not a car person, so, it's black magic to me under the hood.

I believe that's normal for electrically powered refrigeration systems.

Yeah, after I posted that I thought, well, that's how it is on refridgerators and freezers, why would cars be any different?

I was surprised by the small size though. It's barely the size of a 2L bottle in diameter, and half as long.

Any refrigerant for this sort of system will be vapour at ambient temperature (since you were not doing this at -30 C); unless there was something such as a check valve or closed port of the compressor blocking the fluid path to keep the refrigerant under pressure, it wouldn't be liquid; even the liquid would flash to vapour quickly, with the associated chilling effect. Did you get a mouthful of lubricant, rather than refrigerant?

Both presumably.

It was a rocket nozzle for 2 or 3 seconds when I yanked the line out. Had time to spit and wipe my face and look around sheepishly to see if anyone else heard the noise while it was still fwooshing. Soaked the whole front of the engine bay. Most of it evaporated in a second or two.

 

[Duncan]

Why are you looking for a steering and brake booster for a little car like that?
Keep it simple!
Power steering and brakes are completely unnecessary on a small car

 

[brian_]

Why are you looking for a steering and brake booster for a little car like that?
Keep it simple!
Power steering and brakes are completely unnecessary on a small car

I didn't have or need power steering on the compact cars that I had until about a decade ago... but they had relatively slow steering. The quick ratio of a typical power-assisted rack is unsuitable for street use without assist.

Drum brakes when used at the front axle are designed to be "self-energizing", so they don't need boost. Very few vehicles have ever been built for street use with front disk brakes and no assist; our Spitfire is like that, but it is very light. Matt's Opel GT has brake assist, as appropriate for its brakes and weight.

 

[MattsAwesomeStuff]

Why are you looking for a steering and brake booster for a little car like that?

I dunno, I've never driven one, so I don't know how tough it is. I'd like to not have to muscle it around in parkades. I can always turn it off with a flick of a switch.

More importantly, I presume it's collapsible to some degree. The original is basically a javelin pointed at my sternum. It's apparently "collapseable" but I don't know if that's destructively or not. It sure as heck doesn't slide anywhere on its own.

Tilt is also a nice bonus to have.

Also, I just like the idea of stupid simple no-brain electric power steering. In the car-as-a-project sense, versus a result, it's one of the few things that piqued my interests and it seems simple to do.

Power steering and brakes are completely unnecessary on a small car

Steering, if designed for it, which it was.

Brakes not so much. Maybe if I modify it to change the leverage ratios I could go unpowered, but from anyone who's had a vacuum failure, they say it's terrifying to try to stop.

My brake booster is... questionably sealed. It apparently held a seal, but, it's 50 years old and not really serviceable. I don't like the idea of brakes failing at any time. A friend gave me a booster from an Opel Manta, but it needs me to machine an adapter.

Mine on the left, the Manta donor on the right:

Also, the distinct hood blister demonstrates that they really packed everything in as small as they could on the GT originally, and the air filter just had nowhere to go so they had to bulge the hood to fit it. The default location for the booster is bizarrely past the front nose the hood. So there's this long shaft and a protective frame member that crosses through the whole engine bay rather than being mounted to the firewall. Since I don't have the space constraints of the engine, but I do want available space for a frunk or batteries, moving the booster is one of the things most guys have suggested I do.

To remove powered brakes:

• Re-plumb the lines
• Fabricate master cylinder mount/bracket
• Probably not safe
• Extra work to change brake ratios

To keep original powered brakes:

• Re-plumb the lines (lines are broken anyways, I need new ones)
• Fabricate booster adapter
• Fabricate new mounting methods (if I want to remove the long linkage)
• Add 12vdc vacuum pump, reservoir, brackets, lines, wires etc.
• Deal with annoying vacuum pump noise.

This versus, to change over to iBooster electrical brakes:

• Re-plumb the lines
• Fabricate booster bracket
• Add some wiring

Considering the hassles of doing anything to the brakes other than just putting them back the way they were (still have to make new lines), I might as well just design it for something new and modern that's probably less work.

That said, it's not set in stone.