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I'm looking to start piecing together a conversion on my '97 Firebird. I've prepped the car (removed ICE related items) but was hoping to get a little guidance on path forward.

Weight: ~3400
Transmission: T-56 6 speed
Rear axle: 3.42

My goals are:
Range: 40-50 miles
Performance: As much as I can afford
Budget: ~20k to start

Some of the AC kits look interesting, but seem geared towards lighter cars. I wanted to use a Warp 11 with a Soliton 1 because it seems like a simple setup, but after emailing EV West, they no longer sell DC motors and the Soliton1 isn't made anymore. I understand performance really comes down to the batteries but I'd like to start with a solid base and upgrade as the budget allows.

I thought I had a pretty good grasp of what I wanted to build ~5 years ago but now that I'm ready to actually start buying parts I've found things have changed quite a bit in the industry. Is a Tesla swap really all that is out there now?
 

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Hi

For DC you need a P&S IGBT controller (360 volts and 1400 amps) (about $1000)
and an 11 inch forklift motor (I paid $150 for mine)

For a heavy car like yours you could retain the gearbox OR fit two motors and run two controllers

My car (Duncan's Dubius Device) is about half your weight - 805 kg and I am running direct drive

For AC - you are much much better off with re-purposed OEM EV bits
 

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Wow, I hadn't considered putting together my own controller but looking at the Instructable it certainly seems do-able.

I'm back to debating DC vs AC. I'm a little turned off by the Tesla stuff since it seems like a pain to interface with.
 

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I'm back to debating DC vs AC. I'm a little turned off by the Tesla stuff since it seems like a pain to interface with.
It is.

But you have many options.

The new meta is:

Cheap builds: Prius transaxles & inverters (technically capable for 480hp)
Medium builds: Nissan leaf transaxles & inverters
More powerful builds or RWD: Lexus GS450H motor/transmission & inverters
Expensive/performance builds: Tesla

One way or another, there are control boards that were born out of the Open Inverter project that you can now purchase for these, pre-built and tested. There's hardly even any point in buying the kit, they're so cheap to order professionally-made.

Johannes' Open Inverter:
https://openinverter.org/docs/index.html?en_home,3.html

Or Damien Maguire's webshop:
https://evbmw.com/index.php/evbmw-webshop

There's very little product support for them beyond the Open Inverter forums, where the community may try to help you out, or Johannes or Damien may step in as well. If you want support, you can buy boards from a variety of resellers (or, people who avoided even buying them in first place because it's an open source project and they just cloned their own boards), who basically mark the price up 1000% to cover that expense.

As I recall, Johannes' Leaf brain is a replacement for the control board and you can tell the Leaf inverter and motor to do whatever you want (generally well in excess of OEM limits), whereas Damien's solution is less rude and mimics the Leaf's instructions to the inverter but then has the same OEM limits.

Damien recently hit his limit with the pushy Tesla board buyers and abandoned producing both the small and large drive unit control boards. It was a neverending stream of entitlement from the performance crowd that he was tired of dealing with as a volunteer. Johannes offered to pick up service and sales of those boards instead, we'll see how long he lasts but I think Johannes is more comfortable just insisting on a service fee or stop bothering him and figure it out yourself :p.

In new news this week, Damien rolled out a new Prius Gen 3 control board. This one integrates twinning control to both power inverters at the same time for more motor power, or using one as a battery charger.

Meanwhile, Johannes rolled out a Prius Gen 2 adapter (add on) board to his generic Open Inverter control board with some upgraded features from what Damien's Gen 2 kit had. There's a few of us using Damien's 1st batch of Gen2 kits that are more or less a dead end for development now (they were a trial of beginner friendly boards before a far, far cheaper source for pre-fabbed boards was found, so that there's no point in doing it yourself or using the compromise of kludgier through-hole parts and stripped down microcontrollers to get it done). Johannes' new control kit will handle all the Prius Gen 2-specific plugs and extras that Damien's 1st trial batch was missing (like current sensor integration) on a bit more of a proven platform than the stripped-down clone Damien was trying it out on.

...

Honestly, I can't see any way that a DC build is worth doing anymore. It's not cheaper or easier.

The Prius inverters cost like $150 and come packaged with:
- Two high power inverters to run motors, up to 480hp combined with graceful overvoltage/overcurrent/overtemperature failing (unlike Teslas). Or, can use one as a battery charger.
- A boost converter to step up 200v to 500v at driving power (tested but no one's developed a control board to use it yet)
- A 100A DC-DC step down converter (200v-ish down to 12v to run car systems)
- An extra inverter to run an air conditioner motor.

A couple hundred for either Damien's or Johannes' replacement brains (uncertain pricing yet, boards are being tested), and you've got almost everything you need electronic to do your conversion.

I think it's probably worth holding off buying control boards until there's some boost-converter development if that's what you're aiming for. As far as I know you can still hit highway speeds without it (and no need to use it, you can feed the inverter 500v yourself), but, that's the last obstacle for budget builds, which have trouble fitting 500v worth of OEM batteries into their vehicle (since you can't choose half of a cell, you have to choose half of a pack, and will have lower voltage).
 

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For a heavy car like yours you could retain the gearbox OR fit two motors and run two controllers
Speaking of which, if you note the classifieds posted today, there is a twin-motor with Zilla controller for sale for $1500. Already mounted and ready to go.

https://www.diyelectriccar.com/forums/showthread.php/sale-zilla-motor-controller-and-dual-200851.html

That's a fantastic price for something already engineered. Even if you have to pay to ship it on a pallet.

Pretty close to a drop and go solution, driveline-wise.

Alternatively, a Prius Gen 2 controller and Damien's new DC Motor Control board would give you 500v and 375a per phase. That's about $150 + whatever he decides to charge for his control board.

Cheap cheap.

He'll be testing later this week: https://openinverter.org/forum/viewtopic.php?f=14&t=275&p=10928#p10928
 
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