# Using Coda as donor vehicle



## scotmac (Feb 23, 2016)

OK, i just started my EV journey, so be kind.

I have built a lotus 7 style kit car, and i am putting a EV drivetrain into it. I am picking up a wrecked coda fairly inexpensively, and am going to transfer everything i need from it. Some questions:

1. From my calculations, i believe WITHOUT a transmission (direct drive to diff), i still should be able to get up to around 127mph. The diff is 3.91 to 1 and the UQM PP100 specs to 7700 rpm. I used 24.5in outside diam on tires, 7000 max rpm (to be safe), and 4:1 diff ratio. Are my calculations correct?

2. What parts do i need off the Coda? Obviously the motor and inverter and cables, batteries, DC DC converter, and chargers. But what else? Vacuum pump? Is the vacuum assisted braking really needed? How do i hook up the vacuum pump?


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## Duncan (Dec 8, 2008)

Hi Scot

Have a look at my car - sounds similar to what you are trying to do
And No you don't need vacuum brakes or power steering

http://www.diyelectriccar.com/forum...-dubious-device-44370p2.html?highlight=duncan


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## scotmac (Feb 23, 2016)

Hi Duncan, yes, similar from a lotus 7'esque perspective, and the fact that we both are not doing a conversion. But mine is a robin hood lightweight, which is a aluminum monocoque, whereas yours appears to be much closer to the traditional space frame based locost design.

I was looking thru your build thread, and didn't see a lot of details about your motor. What did you use? What is the power/max-rpm's? What is the diff ratio, and how well does the direct drive work? I have seen it quoted many times about how a transmission really saves your batteries. ie, the fact that the high rpm's will eat up your electrons. But from a track/racing perspective, the direct drive has got to be better. less weight, and more power.

What are the details of how you hooked up the direct drive? Are you splined out of the engine or keyed? did you use slip yokes?


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## Duncan (Dec 8, 2008)

Hi Scot
I'm using a Forklift motor
Hitachi - 11 inch diameter weighs 102Kg
It is rated at 10Kw and 48v - 210amps
cost me $100

With 144v and 500 amps it was great fun!

When I went to 1000amps and 130v it was superb - would take off like a scalded rat but was limited to 100kph

It is now going back together with 1200amps and 300+v - Hee Hee
(Chevy Volt battery pack)

I have a 4.1:1 diff and with a big old DC motor I'm limited to about 130kph

The motor had a splined drive with a parking brake on one end - I used the center of the parking brake and made an adapter to go onto a short (very short) propshaft

The advantage of going direct drive is that the motor goes where the gearbox would have leaving the whole "engine bay" for the batteries

The car is a bit overbuilt so it weighs around 720Kg - yours should be a lot lighter

If you have enough grunt direct drive is best


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## scotmac (Feb 23, 2016)

That is a lot of amps...tesla ludicrous style! 

I have no idea what mine will weigh, once i get it loaded up on batteries, like yours. Batteries are definitely heavier than gas! I think i saw the Coda battery pack listed at 700lbs, assuming i use all of it. When i was going to do ICE, my goal was 1000lbs, for the entire car. So, i only have 300lbs left! 

It is a rolling chassis now, with diff and rear drive shafts installed. I would bet it already weighs more than that 300lbs!


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## scotmac (Feb 23, 2016)

So, has anyone used a coda as a donor vehicle? 

If you can get it inexpensively, it saves you a lot of money. If you figure the price for buying the individual parts separately (battery pack, chargers, motor and inverter), you are already double what i am paying for the car itself.


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## Duncan (Dec 8, 2008)

Hi Scot,
They only made about 100 of those - and only sold them in furrin parts 

I would have though a damaged Leaf would have been a better bet

Saying that if there was a wrecked Coda here for sensible money I would snap it up

_If you figure the price for buying the individual parts separately (battery pack, chargers, motor and inverter), you are already double what i am paying for the car itself. 

_I most sincerely hope that you are not paying that much!The battery,chargers, motor, inverter together would be over $25,000


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## scotmac (Feb 23, 2016)

OK, i was figuring used prices of around 12-15k. But ya, if you figure new prices, esp with UQM wanting 14k for the PP100, you could easily get to 25k.


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## scotmac (Feb 23, 2016)

And the leaf is not appealing to me, compared to the Coda. Less battery capacity, heavier less powerful motor, gotta get your own inverter (not hacked by evtv), and don't those leaf batteries have degradation issues?

But they are definitely plentiful!


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## scotmac (Feb 23, 2016)

Just got the coda...paid $6000 for it, for everything (uqm 100 and inverter, 2 chargers, complete battery pack, ...).

Now i just have to figure out how to take it off the coda and put it on the RobinHood Lightweight.

Question: should i use a GEVCU, or should i try to transfer everything (so the coda computers will be happy)? I think the GEVCU would be a lot simpler, but then i have to deal with EVTV Jack.


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## Duncan (Dec 8, 2008)

My tuppence worth
Start off using the lot - if you don't use a GEVCU then you don't have to pay for one!

Once it's all together and on the road - then think about a GEVCU - which will probably be cheaper and more capable by then


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## Electric A1 (Oct 16, 2016)

Any progress on using to Coda drivetrain? I just found an INSANELY cheap wrecked Coda on craigslist in Orange County. Being a college student I wouldn't normally even pretend to have the money to do a conversion on a car, but this one is so cheap I may not be able to pass it up... 
Are there any proprietary programming issues you've dealt with so far with the donor drive-train, and also what sensors have you been able to discard/which are necessary? Those are my main concerns...
Cheers!
Alex


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## Artie (Oct 9, 2017)

Any progress so far?


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## scotmac (Feb 23, 2016)

No real progress. I bought a coda, and it is sitting in my driveway! Unfortunately i decided to start a family instead. Thinking this will be a good project to finish up w/ my son when he gets older.


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