1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Tell us about the project you do with the open inverter
RetroZero
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by RetroZero »

I'll have a look at them, thanks. If anyone has the 'perfect' reference, please share so I can update the wiki, otherwise will go with the link mentioned above. ;)
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

I know I'd said I was going to keep this build log mostly related to electronics and inverter stuff, but, if anyone is bored enough to want to watch 2 hours condensed into 6 minutes of me taking off a front suspension for the first time, here you go:

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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by mike77cos »

What a brilliant project, I watch all the threads and Damian's videos and I feel totally lost, I'd love to do a conversion be I worry I'd make a complete mess of it. But I keep watching and learning, even if 99% goes over my head.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Nothing inverter related, but then, I haven't touched my inverter or the Prius Gen2 throughhole board in 8 months. Update for the sake of updating...

No news like bad news...

Took a close look and noticed some funny coloring on the driver's side.



Trouble is... in the area I *know* to be bad, I can't visually identify it with the scope. So for all I know, most of it is that bad.

I only lightly chain-whipped the outer rocker, pretty hard to get any kind of movement with a narrow triangular cross section, but, maybe better than nothing. Looks like lots of debris knocked loose, but, I didn't chain-whip the inner and it looks exactly the same so maybe not.

Looks like I'll need to patch significant portions of both wheel panels on both sides in the rear, and probably the rearward portion of the front wheelwells too. I expected a couple small patches, looks like I'm in for 6 medium sized patches, and I get to discover how applicable my trigger time welding up the interior is going to be on the exterior where it'll be visible. I predict.... not well. Have a feeling I'm coming on a turning point of a project I can finish, to one I never will.

Rockers on the passenger side don't look as suspicious as the driver's, but, I'll give them the probing too. Not sure what to do about those. Maybe plug the ports with hot glue and fill them with another gallon of evaporust. I suspect the paint is structural in many places, I'll leave a plastic sheet underneath so I don't waste all my evaporust when it escapes. And then, who knows what's left in there.

Rather demoralizing, especially for my first day back working on it after several months, and having wasted all the daylight hours of the summer on other people's vehicles. Back to working under bulb light. Probably has to be fixed to pass out-of-province safety too.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by arber333 »

MattsAwesomeStuff wrote: Fri Sep 11, 2020 11:03 am Rather demoralizing, especially for my first day back working on it after several months, and having wasted all the daylight hours of the summer on other people's vehicles. Back to working under bulb light. Probably has to be fixed to pass out-of-province safety too.
My condolences really. It looked like a very inspiring project.
Still lately i keep hearing some strange noises from my MX3 when i lift it up. I am afraid to inspect the front bridge and side steps.
I have a suspicion there is plenty of rust there... Hiroshima 1992 was obviously a great year, but everything has its limits :).

I suggest to all of others... As first EV conversion, choose a car that is physically in top shape. That will be greater confidence boost when dealing with various EV issues and wiring problem solving.
Another advice would be to get a worhshop as close to home as possible, to allow you to work on your project in small bits every day.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Random philosophy of hobby work tangent below...
arber333 wrote: Fri Sep 11, 2020 12:11 pmMy condolences really. It looked like a very inspiring project.
It's not dead, but... you know how 90% of car projects never get finished? Do those people know after a year that they'll never finish and it'll be abandoned? Usually not.

My line in the sand before was to avoid painting the car. Soon as I'm painting, the "Well, I might as well.." list grows long, and the "I have to do X before I paint, because it'll ruin the paint and I'm not repainting" starts to take over. So every time I was tempted to take out the sander, I'd said no, do what it takes to get it moving, not pretty.

Well, likewise... this went from "home stretch, yeah the wheel wells are rusty but fix the cosmetic stuff later one step at a time when you feel like it, maybe next year" to "you're now only half done your welding and you probably can't pass an inspection unless you do it first".
I suggest to all of others... As first EV conversion, choose a car that is physically in top shape. That will be greater confidence boost when dealing with various EV issues and wiring problem solving.
To as much a degree as I could, that's what I did.

I spent $200 on the car, and $1000 in gas to drive to Arizona and back to pick up a desert car.

And, the rockers aren't in bad shape. Basically anything under $3000-5000 where I am is going to have significant rust damage, and rockers and wheelwells are the typical places.

It's a pick your poison type of thing too. My goal isn't "build multiple EVs", so for me there was no point in a "starter build" situation. I was only interested in a fun car that I wanted to drive. I'm not motivated to work on a project I have no passion for. Otherwise I would have spent that same $1200 on an old Civic.
Another advice would be to get a worhshop as close to home as possible, to allow you to work on your project in small bits every day.
Even if it was just down the street... this has impacted me more than I imagined. Psychologically, I've learned a lot about how motivation and inspiration works for me by starting this project.

I can't schedule my motivation. It waxes and wanes every five minutes throughout the day. I have no idea whether today is going to be a little effort day or a big effort day. I only find out in retrospect.

My workflow is generally: baby steps, baby steps, baby steps, RANDOM BINGE. And I work on stuff every day, or multiple times a day.

Lots of times I've had blocks of time available and wanted to work on the car sometime tonight... just didn't want to work on the car right then. Sure I could have discipline if I have to get something done, but... that's what work is. I don't want it to feel like work, it's something I am doing for fun.

Back when I had an attached garage, I'd pass by the garage on my way to get a glass of water and, unplanned, think "Hey, I'll go work on X right now", and maybe it is only 5 minutes, or maybe that 5 minutes turns into 5 hours because I'm having a great time. There's no penalty for jumping on the motivation of the moment. If I lose interest in 5 minutes, no problem, back to whatever else I was doing.

When faced with the decision of "Do I drive 30 minutes to the shop?" the answer is almost always no. I don't know when I'm in a mood to work on it for 5 hours, and I'd get frustrated driving an hour if it ends up being only 5 minutes. So then I'd stay and work when I wasn't into it, or I'd get nothing done. I'm sure many nights I didn't go work on my car when I would have (in the end) been up for a 5 hour binge, because I only ever know about the next 5 minutes.

The shop is close to my work, which is great in terms of "I'll go there straight after work" and still having some daylight and a short time it's okay to make shop noise, but, that means I have to decide that immediately after a day of doing things I don't want to do. Else I'd go home, and if I go home I'm there for the night. I don't think I've ever gone all the way back, then all the way back home a second time.

Also, I don't have a bathroom at my shop. So, even more frustrating is when I'm really motivated to get stuff done and then being interrupted and having to pack up, close down, go for a (short) drive, come back, open up again, ugh. And I work every day so my availability is only late nights (I love being up at night, that's not the problem), which, I don't like opening and closing the garage door and starting the car up multiple times, kids are asleep in the neighborhood and such. When I'm in the zone on a project, I don't want distractions. 10 minutes of interruption kicks my feet out from under me and I'd often just go home after.

Or the reverse... sometimes I need a quick break. I need to be somewhere else and do something else. Just want to sit down, grab a bite to eat, and get back to it. Or maybe not, maybe I don't get motivated to return, that's okay. I can stop working without penalty. But when it's not my shop and there's nothing else to do there, I don't get that break. There's no couch or kitchen or desk with a computer to give that break.

I wouldn't have thought I was that wishy-washy, but that's what I've learned about myself. Everything else productive in my life is an oppression I force myself to endure, to be useful, which I can... but it's not fun, it's always work. The purpose of this is to give me something to look forward to other than that tension of work. I don't want to hate it by treating it like it's a job. Might as well just get a second job and buy an EV if that's what it is.

What is only a summer's project in terms of hours, has become probably a 2-year project almost exclusively because my shop isn't attached to my house and I can't predict my motivation.

Anyway... I'm not quitting, I'm just less hopeful I ever finish it now.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Well, did some more digging into the rust. Two weeks ago. Trying to stay motivated.

For those that enjoy sped-up rust pokin' 'n proddin':



Image

Few notes:

- Driver's Rocker isn't in great shape, but appears to be worst just in a diagonal line. My guess is that it was parked outside, with the tail lights removed, on a driveway or hill at that angle, until dust settled. Annual Arizona rain rusted a single line through the metal there. The interior rocker has holes at the back but otherwise isn't too bad. I see a line of paint bubbles that seemed solid when I poked them but I'm thinking have to be where the rust bled through to a pinprick. Maybe best to just replace an extra 6" down that line.

- I don't know what those white goopy knobs are inside the driver's side rearmost fender, but, I'd suspected this car was rear ended at some point, lightly. Looks like those might be the fill scabs from dent pulling? Isn't obvious to me from the outside.

- Passenger side isn't nearly as bad, half the damage. Doesn't really matter, a slightly smaller or larger circumference doesn't add too much time, and the damage is mostly in a single plane so no complex curves, low enough that the wheel flares haven't sprouted form the side yet.

- Passenger rocker has no holes at all that I found. Rust spot is from the outside where paint wore off. Camera scope picks up a couple rusty patches inside, but otherwise looks great.

- Front wheelwells and fenders seem intact, couldn't poke a hole anywhere. So damage is confined to the ass end and the driver's rocker.

I'm not even sure where to buy sheet metal from affordably. Had an idea to just take a sawzall to the junkyard and cut the roof off a minivan or something equally sheet-esque. Then I wondered if the metal on a new car is more likely to be paper thin compared the GT. Maybe should try the side of a truck box instead. Maybe older is better? Will have to do that soon, summer is over, fall is here, snow arrives soon.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Finally made a go at casting with Zamak, after my first attempt struggled to maintain high enough temperature with aluminum.



Stunning partial success:

- This is a great way of turning $300 of conduit couplers into $3 of zinc.

- Best cheap source of Zamak I found was in old 2-hole punches. Just had to rip them apart and remove the steel punches and springs. They were a pound and a half each. Towel racks, cheap chromed drawer knobs, banister supports, and a CVT pulley from an old treadmill were all also Zamak.

- Zamak weighs 2.5 x as much as Aluminum. My previous attempt that got the giant airpocket frozen into it was 404g. If that was filled solid it would probably be 40% heavier. All told, I'd need at least 2500g (actually, bad math I notice now, I calculated as if missing 60%, not 40%, oh well). Turns out I had around 4kg of the stuff, so, should have been plenty even after the excessive dross of melting it in a frying pan.

- A heavy duty stainless steel frying pan is not strong enough to lift 10 lbs of zinc. Had to use pliers on the far side to help

- Missed the sprue, sloshed over into the main pour.

- Zamak is 2.5x the weight of aluminum. Buoyancy on that plaster form is now 2.5x as strong. Up it pops like a cork. Nothing to do but finish the pour and spend 2 hours melting it down again. In retrospect, this is like filling a bathtub and expecting the tennis ball to stay at the bottom.

- Form seemed relatively undamaged by the pour, so for shits and giggles, I stuffed it back in the topside, just guessing at where the center was and the correct angle.

- I hit pretty close to center. I hit pretty close to square to the surface of the pour too... except that the mold wasn't square.

- I probably destroyed the motor bearings, but I lightly hammered the coupler onto the motor, and then pried it back off a half-dozen times. The hardened motor shaft is taking just the slightest shavings off of the surface on a half-dozen splines. It's already 2/3 of the way on, I won't press it further until I have a slide hammer or some way of getting it off, it's too deep into the recess to pry it out if I go deeper.

- Surface of the splines seems as good as they ever were in plaster. Zamak is famed for being a zero-machining process, you can capture the surface of a coin accurately if you want, so all imperfections were silicone/plaster based. It's good enough.

- All the excess chunks I cut off showed solid metal all the way through, no porosity.

- The coupler being off-kilter isn't a big deal. It doesn't have to be a 1/2" thick, and certainly won't be at the transmission end.

Overall, Zamak was beautiful to cast with. Stayed glassy smooth for several minutes (off camera) after the pour. I'll have to keep an eye out at the junkyards for old bathroom fixtures and such.

Plan now is to get the motor spinning, (coming up on 1 year since I started working on my Prius Gen 2 control board) and use it with a grinder as a lathe to make the coupler centered on the motor shaft. Then drill it out for the transmission shaft (a drillbit on a rotating workpiece is self-centering... supposedly).

Also, there's an air cavity at the bottom of the splined area, probably from gas escaping from the plaster. It's not critical, and once I have the hole drilled for the transmission tail shaft, I can gouge the sides and repour some zamak just to give it a helping hand and fill the gap, even if it doesn't add much for strength.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Not really much of a progress bump, still too burnt out to try even the simple possible fixes on my inverter. But...

Just before Covid hit a few years ago, someone here had spotted a good Ebay deal for some contactors. I was a fool to only buy 2, he sold out soon after, but I got them for $22.50 each, with free shipping.

Problem was, he outright refused to ship from the US into Canada. So, because like, 80% of Canada lives within 1 hour of the border, we're all kind of used to this, and the massive cost of shipping to get it over the border. So a whole cottage industry has sprung up of "To The Border Shipping". In the little 3 block border crossing towns, there's little warehouses that everyone ships to, and for $5 they hold your package for you to drive down to and pick up yourself. It's often still cheaper than the gas it costs to pick it up, especially for car stuff.

Anyway, the border was closed to driving traffic for like, 2+ years, which went into effect after I bought them and before they arrived. So, my warehouse basically went on vacation and said "Don't worry, no extra charges, when the borders open up you can still pick it up."

Finally, had a friend in the car community making a trip for everyone, so I got my contactors.

Image

IIRC, they're 500amp, 900vdc. 450kw. 600hp. $275 new apparently, I paid $22.50 including shipping.

Again, yes, I was foolish to only have bought 2. I should have cleaned him out. I was thinking they'd be my main contactors, one for my car, one for my motorbike. I was thinking "I'll get something cheaper for my pre-charge relay." Yeah, no.

If I was doing it all over again I'd have bought at least 2 for each vehicle, just for redundancy and full battery isolation, and then, another one for the precharge on each.

Oh well. They'll still do their job.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by Pete9008 »

Not noticed this thread before. You've taken on a big project there with the all chassis welding needed but it looks like you've got the worst bits sorted. Is it just the outer sills that need work now? if so it shouldn't be too much work to fix.

On metal suppliers I've had success in the past buying offcuts from sheet metal fabricators (if you have any local). Unfortunately the days when you could buy small sheets of suitable steel at motor factors seem to be long gone.

Do you still have car scrap yards that you can wander round there? If so I'd be tempted to make a few cardboard templates of the sill curvatures that you need, take them along to the yard and see if you can find another car that is close enough. Once you've identified a suitable donor either chop the bits you need out or buy repair panels.

It's going to be a gorgeous car when you're finished and well worth all the work.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by Pete9008 »

Just came across thishttps://www.opelgtparts.com/ersatzteile ... eller.html. Prices don't look too bad so might be worth a look?
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Pete9008 wrote: Mon Aug 08, 2022 5:42 pmJust came across thishttps://www.opelgtparts.com/ersatzteile ... eller.html. Prices don't look too bad so might be worth a look?
Horrendously expensive to have shipped to North America. Hence why, twice a year, someone in the Opel GT community flies over to Europe to Suselbeck, does a group-buy from everyone who needs stuff, packs it into a big crate, has that shipped, and then reships it back out to everyone once landed.

Almost as good is OpelGTSource, a California-based supplier.

For an esoteric 50-year old car that's never been desirable or expensive (i.e. you can spend $100,000 fixing one up now, to where it's worth about $20,000 max to sell), there's a fairly solid following for them, and almost every part you'd need is available... for about the same cost as Honda Civic parts would cost you.

Even better luck... the lead mod of the community lives in my town, and has put together a local GT Co-op with around a dozen members. There's a barn owned by another member, who lets it be used for free for storage (and, I've been friends with that person for 10 years, and either they'd never mentioned it before, or, not being a car person, I just tuned out of the conversation when they did. I joined the co-op before I found out they were even involved).

When someone finds a car cheap, they strip it down, and put the parts in the co-op, and then anyone in the co-op can "buy" parts for it at whatever the book rate is for that part, which is usually set to about 1/3 of the part's cost from OpelGTSource. Everyone who buys into the Co-op pays for their percentage share of the Co-op, based on how much people have spent on parts over the years and the current value of the inventory. When you leave, the co-op buys you back out, though, I don't think anyone's actually asked to get paid out, they just donate it as a thank you for doing all the admin work. I think I spent $300 to join, and, sold my gas tank and a few other parts to the co-op, and, have bought a transmission ($30?) and a few others bits and pieces. If there was a world lottery for where you wanted to end up as an Opel GT fan, right where I happen to live is the jackpot.

All coincidence. I chose an Opel GT because I saw one in a yard when I was buying winter tires for my SUV. It was already sold but I was like "Aha, I like that, what is that called? I want one."
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by Pete9008 »

That's a real stroke of luck with the local support! Can't understand why these cars aren't more desirable. I've never come across them before (wondering whether they were ever sold in the UK?) but the shape really works for me and the small size and front cross section makes it an ideal conversion. Are you going to keep the original axle and suspension?

If you can get proper repair panels it's worth it. I've tried to create curved shapes from flat sheet in the past and have always been surprised by how long it takes, how difficult it is and always a little disappointed by the results. The one thing I've found that does help it to really take time when welding the panel in - use lots and lots of spread out spot welds (with time in between to allow things to cool) which slowly merge into a continuous bead . If you try and run a bead the heat causes expansion of the metal and distortion of the panel which then gets set in place by the continuing bead. I'm always surprised by just how much metal moves around when welding and once it's happened it is very difficult to fix and can mess up the surrounding panel too.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Pete9008 wrote: Wed Aug 10, 2022 11:34 amAre you going to keep the original axle and suspension?
In the interests of simplifying to succeed, yes.

I've dreamed about doing a BMW IRS swap, or a Volvo 240 diff/axle, or a Miata, or a Prius front end (it currently has a single front leaf spring), but, the car I can drive handles a lot better than the "better" car up on blocks.

Of particular concern is the pointlessness of using the massive 250lb motor I've chosen. It's heavier than the original engine with all of its accessories. Anything more than the 80-100hp put to the rear wheels better break them loose, else it's sheering the teeth off of the diff gears and twisting the torque tube.

A Toyota MGR or Outlander rear swap is most likely in the future.

My first challenge was "build an electric car from garbage or unwanted items", so, I'd like to see the forklift motor through to a driveable vehicle first anyway.
If you can get proper repair panels it's worth it.
Ha. The "panels" are: Hood, Doors, Headlights. The rest is a single solid monocoque.

You fix a "dented" panel with a grinder and welder.

I've been following Fitzee's Fabrication youtube channel for a few years now, everything he does is welder and grinder, breaks complex shapes into simple, simple tasks, even if it takes longer. I think I'm ready to tackle it. We'll see how it goes.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by Pete9008 »

MattsAwesomeStuff wrote: Wed Aug 10, 2022 6:13 pm I've dreamed about doing a BMW IRS swap, or a Volvo 240 diff/axle, or a Miata, or a Prius front end (it currently has a single front leaf spring), but, the car I can drive handles a lot better than the "better" car up on blocks.
Been reading up a little more on the GT and the more I read the more I like it. The suspension is a lot better than I expected. Yes it has a front leaf spring but it also has double front wishbones, disk brakes, an anti roll bar and rack and pinion steering. It also looks like it would be a fairly straightforward to convert to coil overs if you preferred them to the leaf spring. Can't comment on the geometry but if set up properly it should handle well.

The back looks pretty good too. Live axles aren't quite as good as independent suspension on rough surfaces or in terms of unsprung weight but on a reasonable road you would struggle to tell the difference. I have a kit car that with a live axle (and drum brakes) and while an IRS rear end might improve the ride slightly I'm not convinced it would be worth the hassle. The axle setup is a little unusual on the GT, I've not seen a torque tube used like that before, but it should locate the axle pretty well.

Overall I'd say the suspension on that car is pretty good and if set up right should handle nicely. It looks better than a lot of sports cars of similar vintage.

As an aside the Smart roadster that I'm converting has mcpherson strut front and dedion rear with drum brakes (which I'm not planning on changing) so on paper it's no better than the GT despite being 30yrs younger!
MattsAwesomeStuff wrote: Wed Aug 10, 2022 6:13 pm Of particular concern is the pointlessness of using the massive 250lb motor I've chosen. It's heavier than the original engine with all of its accessories. Anything more than the 80-100hp put to the rear wheels better break them loose, else it's sheering the teeth off of the diff gears and twisting the torque tube.

A Toyota MGR or Outlander rear swap is most likely in the future.

My first challenge was "build an electric car from garbage or unwanted items", so, I'd like to see the forklift motor through to a driveable vehicle first anyway.
Not convinced an Outlander or MGR would be that much of improvement and the conversion to IRS would be a lot of work. In terms of weight do you need a transmission, would that motor have enough torque to drive the diff directly?
MattsAwesomeStuff wrote: Wed Aug 10, 2022 6:13 pm I've been following Fitzee's Fabrication youtube channel for a few years now, everything he does is welder and grinder, breaks complex shapes into simple, simple tasks, even if it takes longer. I think I'm ready to tackle it. We'll see how it goes.
Not seen those but will have a look. I watched this recently https://youtu.be/_3xD6i5nLVY, a lot of it is using an english wheel (one of a list of tools I would love to have the space for, and the time to learn to use, but can't see happening any time soon!) so may not be useful but his explanation of the underlying principles of shaping metal is very good.

Also just realised that your post on the bodywork is coming up to 2years old, have you been able to do anything on it since then?
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

Pete9008 wrote: Wed Aug 10, 2022 9:02 pmIt also looks like it would be a fairly straightforward to convert to coil overs if you preferred them to the leaf spring.
No, that's one of the common "I'll just do this" comments and, everyone gets told no, it won't handle the load, that area isn't designed for that kind of load. It's meant to hold the slight added forces of shock absorption, not carrying the weight of the car on the springs which is transmitted through a crossmember down below. Not much more than tinfoil up at the shocks. And there's no 'frame' to tie it to, it's just cosmetic sheet metal far as the eye can see.
Not convinced an Outlander or MGR would be that much of improvement and the conversion to IRS would be a lot of work. In terms of weight do you need a transmission, would that motor have enough torque to drive the diff directly?
The motor has got to be plenty powerful enough. I'm planning on ditching the transmission, but keeping the tail shaft of the transmission, because that's where the speedometer cable mounts and I'd like to re-use as much of the gauges as possible. I like electromechanicalness. Also it's a convenient hookup to the driveshaft.

So, can't directly connect to the torque tube though. The motor is so large I can't stuff it that far back into the transmission tunnel, so I need like, a 6" housing anyway.

And then, because I need room for the motor/shaft coupler, I need to fabricate some kind of housing, which has to be square and true.... at which point I've been somewhat considering how foolish it is to not just use the existing transmission. I'm not saving that much weight or space. Like, 2-3".

... this thread is actually really sparse, has maybe 10% the content compared to my one on the DIY EV forums ( https://www.diyelectriccar.com/threads/ ... st-1039477 , mostly about the conversion process ) or the OpelGT forums ( https://www.opelgt.com/threads/matts-el ... st-1400633 mostly about the restoration process). Each community I'm in, I try to tailor the content to what that community is interested in, because that's my way of giving back to those that give advice. Here, I try to keep it mostly just about electronics and the inverter. Also because I really need help with my inverter, and don't want to distract or overwhelm the crowd with details about non-inverter things. Like Porkins said, "Stay on target!"

Anyway...

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Also just realised that your post on the bodywork is coming up to 2years old, have you been able to do anything on it since then?
I got burned out after really pushing hard to "finish the welding" and then discovering how bad the wheel wells were. I was already burning out, but doing that "it's okay, there's a goal!" and then the goal evaporated.

And, I was neglecting other parts of my life, and said no more car distractions, get that stuff done (spoiler, 2 years later, still not done).

And then my car got stolen with much of my tools and that kicked my motivation out from under me.

Spoiler, 2 years later... a couple days ago I got broken into again and someone stole most of my tools... again.

So no, haven't done anything on it in 2 years other than pretending like buying parts counts as "progress".

To make a list:
- Got a second transmission with the newer of the tailhousing styles (no 90-degree gear for the speedo needed).
- Got a Prius gen 2 battery for $30. Would only give me 5 miles range, but more importantly, throw it in the back and it's a solved problem for testing. No need to make battery pack decisions before testing car. Also, can re-use safety plug and some relays.
- Prius HV cables.
- Prius electric powered steering.
- Prius Gen 3 inverter (just in case, it was only $50).
- Bunch of Prius coolant pumps and reservoirs.
- Prius throttle pedal.
- Had headlight rotators expertly rebuilt and re-chromated. Including some hidden stuff that was broken. It's the coolest part of the car (no other car has sideways rotating headlights, and it's entirely manually operated via linkages and levers) so I just wanted it done right and lasting forever.
- Prius Gen 2 AC compressor and lines (no inverter).
- Prius Gen 3 AC compressor and lines (built-in inverter)
- Prius Gen 2 evaporator, and, actually the entire heater box/hvac. In case I want AC.
- 2 big contactors finally arrived.
- Pulled 20-some fluorescent light fixtures out of a dumpster and stripped them down to sheet metal, looks to be 22g, same as the body, so I can start to patch.
- Some 4 months on/off of me trying to get my inverter working in another thread here.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by Pete9008 »

MattsAwesomeStuff wrote: Thu Aug 11, 2022 6:14 am No, that's one of the common "I'll just do this" comments and, everyone gets told no, it won't handle the load, that area isn't designed for that kind of load. It's meant to hold the slight added forces of shock absorption, not carrying the weight of the car on the springs which is transmitted through a crossmember down below. Not much more than tinfoil up at the shocks. And there's no 'frame' to tie it to, it's just cosmetic sheet metal far as the eye can see.
Fair enough, I'd stick with the leaf then. Given that it's only being used for springing not location there realy is not much benefit in coil springs. About the only benefit I can think of is ease of adjusting ride height and spring rates but that's not worth the hassle of reinforcing the structure.

MattsAwesomeStuff wrote: Thu Aug 11, 2022 6:14 am The motor has got to be plenty powerful enough. I'm planning on ditching the transmission, but keeping the tail shaft of the transmission, because that's where the speedometer cable mounts and I'd like to re-use as much of the gauges as possible. I like electromechanicalness. Also it's a convenient hookup to the driveshaft.

So, can't directly connect to the torque tube though. The motor is so large I can't stuff it that far back into the transmission tunnel, so I need like, a 6" housing anyway.

And then, because I need room for the motor/shaft coupler, I need to fabricate some kind of housing, which has to be square and true.... at which point I've been somewhat considering how foolish it is to not just use the existing transmission. I'm not saving that much weight or space. Like, 2-3".
If you are keeping the transmission then using an Outlander motor (just the motor not the gearbox), or something similar, is an option and would probably save you around 100lb. I suppose the question is will your current motor work with your inverter, if it does it would make sense to stick with it. Assume that's why you're currently trying to get the inverter working? If there is anything I can do to help with that let me know.
MattsAwesomeStuff wrote: Thu Aug 11, 2022 6:14 am ... this thread is actually really sparse, has maybe 10% the content compared to my one on the DIY EV forums ( https://www.diyelectriccar.com/threads/ ... st-1039477 , mostly about the conversion process ) or the OpelGT forums ( https://www.opelgt.com/threads/matts-el ... st-1400633 mostly about the restoration process). Each community I'm in, I try to tailor the content to what that community is interested in, because that's my way of giving back to those that give advice. Here, I try to keep it mostly just about electronics and the inverter. Also because I really need help with my inverter, and don't want to distract or overwhelm the crowd with details about non-inverter things. Like Porkins said, "Stay on target!"
Just had a look at your opegt posts, hadn't realised how much you have had to do on this! Well done for sticking with it.

MattsAwesomeStuff wrote: Thu Aug 11, 2022 6:14 am I got burned out after really pushing hard to "finish the welding" and then discovering how bad the wheel wells were. I was already burning out, but doing that "it's okay, there's a goal!" and then the goal evaporated.
Been there, done that, not nice at all. Sometimes you just need to step away for a while and wait for the desire to do it to return.
MattsAwesomeStuff wrote: Thu Aug 11, 2022 6:14 am And, I was neglecting other parts of my life, and said no more car distractions, get that stuff done (spoiler, 2 years later, still not done).

And then my car got stolen with much of my tools and that kicked my motivation out from under me.

Spoiler, 2 years later... a couple days ago I got broken into again and someone stole most of my tools... again.
Really sorry to hear that, hope you have managed to get everything sorted out.
MattsAwesomeStuff wrote: Thu Aug 11, 2022 6:14 am So no, haven't done anything on it in 2 years other than pretending like buying parts counts as "progress".

To make a list:
- Got a second transmission with the newer of the tailhousing styles (no 90-degree gear for the speedo needed).
- Got a Prius gen 2 battery for $30. Would only give me 5 miles range, but more importantly, throw it in the back and it's a solved problem for testing. No need to make battery pack decisions before testing car. Also, can re-use safety plug and some relays.
- Prius HV cables.
- Prius electric powered steering.
- Prius Gen 3 inverter (just in case, it was only $50).
- Bunch of Prius coolant pumps and reservoirs.
- Prius throttle pedal.
- Had headlight rotators expertly rebuilt and re-chromated. Including some hidden stuff that was broken. It's the coolest part of the car (no other car has sideways rotating headlights, and it's entirely manually operated via linkages and levers) so I just wanted it done right and lasting forever.
- Prius Gen 2 AC compressor and lines (no inverter).
- Prius Gen 3 AC compressor and lines (built-in inverter)
- Prius Gen 2 evaporator, and, actually the entire heater box/hvac. In case I want AC.
- 2 big contactors finally arrived.
- Pulled 20-some fluorescent light fixtures out of a dumpster and stripped them down to sheet metal, looks to be 22g, same as the body, so I can start to patch.
- Some 4 months on/off of me trying to get my inverter working in another thread here.
I do think you are almost there on the inverter, all the bits seem to be working in isolation, and you now have all the other bits ready to get stuck in when it does all work.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

This is a bump for EV8 who was curious about my coupler casting. Just scroll up a few posts for the breakdown/video. Or, click this: viewtopic.php?p=17120&sid=d0b88d57bb951 ... ab8#p17120

In other news, to crosspost from the Blue Pill board thread, I got my inverter working:

https://i.imgur.com/mPdlpqk.mp4

... onto the next thing.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by arber333 »

MattsAwesomeStuff wrote: Fri Dec 16, 2022 1:52 am This is a bump for EV8 who was curious about my coupler casting. Just scroll up a few posts for the breakdown/video. Or, click this: viewtopic.php?p=17120&sid=d0b88d57bb951 ... ab8#p17120

In other news, to crosspost from the Blue Pill board thread, I got my inverter working:

https://i.imgur.com/mPdlpqk.mp4

... onto the next thing.
Really nice. Working in manual mode? You want to feed it more % amps and more Hz for more satisfaction :).
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

arber333 wrote: Fri Dec 16, 2022 6:13 am Really nice. Working in manual mode? You want to feed it more % amps and more Hz for more satisfaction :).
It was being powered by a 6A max car battery charger, that tripped its internal breaker when I tried to push 5hz unloaded at it.

So... yes.

I guess before I take it off the bench and down to the shop where I don't have net access, I should actually test the rest of the system outside of manual mode. Try it with a throttle, etc. Because I'm probably getting ahead of myself, and I actually have 200 questions about why it's not working properly first.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by janosch »

THIS IS INCREDIBLE.

I didn't know they ever sold Opel GT in North America, I thought back then everybody would just get a Corvette instead over there.

You have to make this work. You will feel like a god when you go around the block in it for the first time.

Are you the first one to make it an EV?
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by arber333 »

MattsAwesomeStuff wrote: Fri Dec 16, 2022 8:06 am It was being powered by a 6A max car battery charger, that tripped its internal breaker when I tried to push 5hz unloaded at it.
Well i advise you to at least use a 25A household B type auto fuse and provide some 200V to inverter. Perhaps using a Prius battery if you dont have anything else.

But you could be using an autotransformer with 100A diode bridge to rectify ac voltage. Then you could get some 300V and the system would be even happier.
I like solar connectors with the battery because i cant reverse them 😁.

The trick with manual is to open amps to 25% provide some 3hz to spinup the motor and then increase amps to 50% increase slip to 5hz and then 75% amp should feed enough to get you through to 30hz. BUT you need to set fslip sensibly because this is your motor torque knee and it defines its current draw from start. I suggest 100hz at first.
Ah the days of acim motor control...
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

janosch wrote: Fri Dec 16, 2022 4:36 pmI didn't know they ever sold Opel GT in North America,
70% of them were sold in the US. At Buick (GM) dealerships. Buick is the old man brand. Can't imagine a worse pairing.
I thought back then everybody would just get a Corvette instead over there.
Corvettes were more expensive.
You have to make this work. You will feel like a god when you go around the block in it for the first time. Are you the first one to make it an EV?
No, there was a guy who made a white one 15 years ago. Moderately famously so.
http://www.evalbum.com/3548


And, they actually had a factory one made back in the late 60s or early 70s if you can believe it. Lead acid batteries filing every bit of space (including a rectangular rack in the passenger seat), hideous wheelwell covers, and gigantic bedframe worth of nichrome as the "speed controller". But, I suppose you have to remember they made it around the time of the moon landings. Forklifts at the time were using single SCR & capacitor "speed controllers" or just series/parallel switches, transistors barely even existed. The motor in there is a Bosch and it's enormous, it's gotta be like a 13" or 15" motor (actually it's two motors!), ludicrous:

https://www.media.stellantis.com/em-en/ ... elektro-gt

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...

Oh, and one more. Here's a 45-year-old EV conversion, written about 30 years ago in Mother Earth magazine someone linked today:

https://www.motherearthnews.com/sustain ... z93jjztak/

It has some pretty laughably outdated advice (36 volts is the best! You want to buy an aircraft starter motor. A lawnmower engine will help supplement your range!) in modern context. Also some very modest specs. 45 mph top speed it looks like, maybe 50 with the engine running. 25 miles electric range (at 45 mph, half the power to go 60mph).

Apparently he put 100,000 miles on it in the 14 years he'd driven it before the article was even written. And in the first year since they covered it, apparently 60,000 people had written in asking for plans.

...

And, since I've started mine, there's even someone in the same damned city as me who independently came up with the idea.

Also, as luck would have it, the chief admin of the OpelGT forum community also runs the local OpelGT parts co-op, and, someone I've known for years and never knew that side of him, has a barn that gets used as the co-op's parts storage, where there's many of just about every OpelGT part archived on shelves for us to pick up for pennies on the dollar. Like, of all the places in the world for a cheapskate to own an OpelGT, I hit the jackpot.
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

To quote myself 5 months ago:
MattsAwesomeStuff wrote: Wed Dec 14, 2022 7:10 pmNext up I guess clean up my storage unit, move the inverter down there and see if the big forklift motor I picked up 4 years ago actually works. So far just tested with the 100lb pump motor, not the 260lb traction motor.
- Spent a few weeks condensing all my tools (formerly in 5 locations) into a single room. Why do I have 7 giant crescent wrenches? Why do I have 9 caulking guns? Why do I have 4 autodarkening welding helmets? Etc etc etc. Ugh. I mean I know why, garage sales, and I was never sure where everything was, until now. Well, it's all together now, and that's a good start.

- Added some shelves in my small concrete parkade storage room (5' x 8'), along with all my car parts. Got a few feet of workbench to tinker with now too.

- Joined the property's board of directors, replaced the previous busybody management with new management, helped rewrite the 1000-stall parkade policy, deleted the parts about not being allowed to work on vehicles and that all vehicles must be plated and insured. Hurray politics.

- Discreetly ran a cat-5 wire hundreds of feet around past the maze of infrastructure from my property to my storage room, so I have internet access and can install a camera that'll let me know if someone's breaking in (been broken into 12 times). Had permission to do so, years ago, but never got it in writing, so, discretion was of value.

- Discreetly changed a light fixture that now has an outlet on it, to run tools/camera/laptop/chargers. Again, had permission once upon a time.

- Sprayfoamed a couple dozen holes in the concrete, added door seal foam, rubber door sweep, etc, and now storage room is air tight enough it's impossible to slam the door. Power tools running inside are almost silent to someone outside. Not that it's as big of a deal now that the policy is changed, but, it's good to not annoy anyone into changing it back.

- Found some beefy modular terminal blocks I'd been saving for 10 years for just the right time. The time is now. 3 for my motor phase wire connections, 2 for HVDC, 2 for 12v DC. And, all the correct motor wires and HV wires from the Prius itself (which, on the test bench, need to go to terminal blocks for now). No more random gator clips and wires wedge under screws.

Finally ready to start working on the car again.

... but of course, things can't go well...
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Re: 1970 Opel GT - Forklift ACIM - Project Log & Inverter Build

Post by MattsAwesomeStuff »

MattsAwesomeStuff wrote: Fri Apr 14, 2023 9:15 am... but of course, things can't go well...
... What an ominous lead in to what I think was supposed to be a follow-up post, that I apparently never wrote.

My inverter died, I think. Which was okay, because I had a spare, so I swapped over and never bothered to troubleshoot. I think that was the "things can't go well" part.

What a jerk I am. The whole point of that last update was supposed to be a lead in to "Despite setbacks I finally got my motor running".

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Then, after some trials and tribulations casting a coupler, then finding a good deal on a matching spline and machining a coupler from it instead, I assembled it all last night and gave it my first test spin up to 150hz (3 pole pairs, so, ~50hz on the motor, 3.44 gearing, 2m tire circumference, need 13.9hz on the tire to be 100km/h).

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