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Discussion Starter · #41 · (Edited)
Well, I finally got the engine and transmission pulled. I started cleaning up the engine bay and removing non-essentials. I also loaded the motor and dropped it off at the machine shop so they could make sure the bolt holes are exactly like I want them. All this stuff was a lot to muscle around in an evening, but the hard stuff is almost over!

I picked up a 2 ton hoist off a trading site, so I was finally able to get this bit finished.


I have another question that I'm struggling with, however. As far as the 12 volt system, the battery is charged from the DC-DC converter. Do I need to do anything special, or can I just wire the converter to the battery terminals, and the battery to the system as normal? I believe there's some kind of regulator traditionally used with an alternator. Does that setup need to be replicated to safely charge the 12v battery from the converter? I'd also kind of like to go with a lithium battery for the weight savings, but I'm unsure what capacity I would need. I really haven't made any decisions in this area yet, so it's all up in the air.


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The original lead acid starter battery is more than you'll need in terms of weight and capacity. I used a U1 lawn tractor battery- works perfectly, and drops the weight a fair bit.

If I were to do my project again I'd likely ditch the DC/DC entirely in favour of a slightly larger lead-acid or Li ion pack which is charged whenever the main pack is charged, just to save a few dollars and to ensure perfect isolation between the high and low voltage systems. But the DC/DC needs no special regulator- it is a regulated power supply, so its output can just be put in parallel with the battery terminals (with a fuse to protect the wires) and you're done. The lead acid experts here may have a more knowledgeable opinion, but since I only drive mine spring through fall I also take it out and put it on a maintainer over the winter- that gives it a 14.4V "balance charge" about once a month or so to keep it from sulphating. Almost 4 years and still on my 1st lawn tractor battery- so far, so good.

The Chevy Volt BMS has been hacked- if I were to re-do my project with Volt batteries I'd be getting a hand from someone to help me read the data directly from the Volt BMS over CANbus- that's the cheapest option by far, and an OEM BMS is going to likely have more durability than the low volume ones intended for the DIY market.
 

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Discussion Starter · #43 ·
The original lead acid starter battery is more than you'll need in terms of weight and capacity. I used a U1 lawn tractor battery- works perfectly, and drops the weight a fair bit.



If I were to do my project again I'd likely ditch the DC/DC entirely in favour of a slightly larger lead-acid or Li ion pack which is charged whenever the main pack is charged, just to save a few dollars and to ensure perfect isolation between the high and low voltage systems. But the DC/DC needs no special regulator- it is a regulated power supply, so its output can just be put in parallel with the battery terminals (with a fuse to protect the wires) and you're done. The lead acid experts here may have a more knowledgeable opinion, but since I only drive mine spring through fall I also take it out and put it on a maintainer over the winter- that gives it a 14.4V "balance charge" about once a month or so to keep it from sulphating. Almost 4 years and still on my 1st lawn tractor battery- so far, so good.



The Chevy Volt BMS has been hacked- if I were to re-do my project with Volt batteries I'd be getting a hand from someone to help me read the data directly from the Volt BMS over CANbus- that's the cheapest option by far, and an OEM BMS is going to likely have more durability than the low volume ones intended for the DIY market.


Thanks for that insight! I had considered using the Volt BMS, but I couldn’t find much information, and it seemed to me that it would probably give me a bunch of trouble since I’m only using a portion of the pack.

I will look again and see what I can find.

I figured a small battery would probably work, but I wanted to be sure. I want to go with a converter so that I can run more accessories in the future should the need arise. Thanks for that as well!


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Discussion Starter · #44 ·
Well, the DC control board came in over the weekend. I’m very excited to start building the controller! I still need to purchase the current sensors, a thermistor, and the small converter to power it. I also need the raw metal for the base and case.

My charger also shipped (finally). I’m looking forward to getting some of this stuff in hand so I can mock it up.

And lastly, my mounts for the motor will be ready very shortly. I bought a generic ring mount for the back from an EV shop, and had a local machine shop make the front plate.



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Discussion Starter · #45 · (Edited)
Big day for the project! I picked up the front mount and mocked everything up. This allowed me to measure the location of the driveline. It needs to come up between 2.5 and 3 inches to clear to my satisfaction. It will fit perfectly, based on my measurements.

The fan is a little close right at the back, but it fits. Once it comes up a couple inches, it will clear easily.

I’m getting a ring to mount around the middle/back of the motor, and I’m planning on mounting the brackets to a single, long piece of rectangular stock, one for each side. I’ll then bolt the stock to the frame.
I’m hoping to mount the volt batteries on top of/in front of the motor, but I think it will be a tight fit.

Excuse my immensely messy garage




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Discussion Starter · #46 ·
Got some goodies today.


The charger is much nicer than I anticipated, and the capacitor is huge! The instructions for the charger kinda suck, though.

I’m hoping to put in an order for the rest of the bits to build my controller and get the car moving over the weekend.


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<snip>

The charger is much nicer than I anticipated, and the capacitor is huge! The instructions for the charger kinda suck, though.

I’m hoping to put in an order for the rest of the bits to build my controller and get the car moving over the weekend.


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I got the same Charger from Alibaba, came with chinese instructions, but found this instruction in english on internet. (link below) I ordered mine without CanBus & my Zeva BMS controls it via the enable lead, Works as advertised.

http://goingbush.com/ptev/3.3charger.pdf
 

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Discussion Starter · #48 · (Edited)
I got the same Charger from Alibaba, came with chinese instructions, but found this instruction in english on internet. (link below) I ordered mine without CanBus & my Zeva BMS controls it via the enable lead, Works as advertised.

http://goingbush.com/ptev/3.3charger.pdf
Thanks for that! I found those instructions last night when looking about. Quick questions for you: which hole does each letter on the plugs correspond to, since you have yours running? The letters fall right in between the holes, so it's kinda tough to tell!



I'm preparing to plate some orders for components, and I'm still trying to figure out a good dc-dc converter. This one seems like the most cost effective, but I'm not sure that it's sufficient because the listing doesn't mention if the converter is isolated:

https://www.mouser.com/ProductDetail/?qs=%2b6mEGs9UJHwFxUHUNq/DMw==

This other one is isolated, but costs twice as much:

https://www.aliexpress.com/store/pr...482.html?spm=2114.12010612.0.0.72ecf4d8VPAFjI

What do you think?

I'm getting the driveshaft components ordered as well, and I decided to move to 1310 ujoints for the new shaft instead of the tiny ones that came stock.

For reference, I'm planning on using these components for the drive shaft, listed in order from the diff towards the motor:

Differential flange to driveshaft flange: Spicer 2-2-899-1

Driveshaft end to flange yoke: Spicer 2-26-347 (2 inch tube, .120 tube wall thickness)

Driveshaft tube shaft to slip yoke: Spicer 2-40-1701 (2 inch tube, .120 tube wall thickness, 16 spline male)

Driveshaft slip yoke to motor yoke: Spicer 2-3-8021KX (16 spline female)

Motor to yoke end: Spicer 2-4-503 (1.125 shaft, .25 keyway)

Moving right along!

EDIT: I just saw this... that makes it more clear!
 

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JB, if you measure the pins coming out of the charger A&D are linked ( to traction pack +ve ) and B&C are linked (Negative) - It would have been nicer to use a 2 pin connector . Chinese ... meh !!

I knew I drew a diagram & serached through my notes then found it on the back of my notepad, I think you worked it out but for whiw

 

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The first DC-DC converter you listed would not work for me, Im converting a 4x4 I need water -resistant splash-proof .

( I never saw the second one - it would be fine I guess)

I found what I thought was an absolute bargain, and when it arrived I was so impressed I bought another as a spare or incase I decide to piggyback, but since I don't drive at Night I think 50A is plenty , (especially considering my old Alternator was only 35Amp)

https://wholesaler.alibaba.com/prod...l?spm=a2700.7724838.2017115.11.75624613S5uOeo
 

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Discussion Starter · #51 ·
JB, if you measure the pins coming out of the charger A&D are linked ( to traction pack +ve ) and B&C are linked (Negative) - It would have been nicer to use a 2 pin connector . Chinese ... meh !!



I knew I drew a diagram & serached through my notes then found it on the back of my notepad, I think you worked it out but for whiw





Ah, that’s good confirmation. Thanks!



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Discussion Starter · #52 ·
The first DC-DC converter you listed would not work for me, Im converting a 4x4 I need water -resistant splash-proof .

( I never saw the second one - it would be fine I guess)

I found what I thought was an absolute bargain, and when it arrived I was so impressed I bought another as a spare or incase I decide to piggyback, but since I don't drive at Night I think 50A is plenty , (especially considering my old Alternator was only 35Amp)

https://wholesaler.alibaba.com/prod...l?spm=a2700.7724838.2017115.11.75624613S5uOeo


I would love to use one of those, but my battery pack will be at 196.8v when charged, and that seems to go past the limits of most 144v converters. I’ll check what’s listed on alibaba, though. Thanks!


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Discussion Starter · #53 · (Edited)
So I’ve got the dc-dc sorted out - I got one from the same folks that I got the charger from. I also got the driveshaft in, so I had a shop cut, weld, and balance it yesterday. I got that installed this morning and hooked the motor up to an old car battery. Everything turns very nicely :) it was easily able to move on just the flat battery.

I want to change the oil in the diff at some point, and I probably will soon now that I can drive it onto ramps!

The controller is nearly completed. I got my copper last night, and I should be getting the nomex today.

I also have the “fuse box” nearly wired, since I’m rewiring the entire car. Bleh.

Lastly, I got the evms and monitor from Zeva.

I’m still looking for a suitable reversing contactor, if anyone has recommendations.

It’s been a busy few weeks!




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Discussion Starter · #54 ·
Well, I’ve made a ton of progress. Almost everything is wired up, most of the interior is done, most of the gauges work and all the lights and switches function. The batteries are mounted in the trunk, controller and dc-dc are mounted in the engine bay. ZEVA BMS is functioning, and the charger is working. I’m waiting on a control board and some wire to button everything up and drive the car, essentially.

Here are a few pics:



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Discussion Starter · #55 ·
To close this out for now, it runs and drives. It still needs a lot of work, but I'd chalk this up to a big success at this point. This video is taken gently rolling up to just under half throttle, and it's very, very fast. It has a considerable advantage over my supercharged '66. So that's fun.

 

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Well, I’ve made a ton of progress. Almost everything is wired up, most of the interior is done, most of the gauges work and all the lights and switches function. The batteries are mounted in the trunk, controller and dc-dc are mounted in the engine bay. ZEVA BMS is functioning, and the charger is working. I’m waiting on a control board and some wire to button everything up and drive the car, essentially.

Here are a few pics:



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So, now I'm confused. Your controller looks like it has three wires going to the motor. Is this part of the motor reversing system? Although, it looks like you have a 2 contactor reversing system in the gray box.
 

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Hi
It's the Paul & Sabrina high power controller

My understanding (which could be wrong) is that one of the problems with using several IBGT's is getting them to share the current nicely
Paul's ingenious solution is to have each one with a length of cable of it's own before the three join together - this gives a small resistance and a small voltage - enough to balance the three IBGT's

On that point
What current are you using? - I have mine set to 1200 amps
 

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Discussion Starter · #60 ·
Hi
It's the Paul & Sabrina high power controller

My understanding (which could be wrong) is that one of the problems with using several IBGT's is getting them to share the current nicely
Paul's ingenious solution is to have each one with a length of cable of it's own before the three join together - this gives a small resistance and a small voltage - enough to balance the three IBGT's

On that point
What current are you using? - I have mine set to 1200 amps
I have it limited to 1000 amps with my K11. The axle wrap is so bad, however, that I'm not comfortable accelerating very quickly at the moment. It gets really gnarly between 500 and 600 amps. The whole nose of the diff lifts several inches and throws everything out of alignment. I'll be putting on some traction bars and checking that everything is tight on Wednesday. I can't wait to really give it a go, it's a rocket ship.

Between 0 and 300 amps, however, it's very peppy and smooth. Quite pleasant, actually. Cruising amps around 40 are lower than I thought they would be, as well.
 
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