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E-E30 BMW Build

39K views 46 replies 13 participants last post by  eBIMMER 
#1 ·
I have been working on my car for a while and using this forum as one of my primary references. I thought it was about time that I posted my progress and documented my build.

Donor car: 1990 BMW 325i
Voltage: 156V
Batteries: 13 12V AGM Lead Acid
Range Target: 30+ miles
Top Speed: 70+mph

I bought the car in February, but didn't really get into the build until September. I spent the time from February to September finding parts and designing some of the adapters, couplers, etc.

I am going to be attaching quite a few pictures. Below is a pic of the car as I got it, without the engine. I cleaned up the engine bay and removed the sound deadening material.
 

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#40 ·
Everything is working great and I now have 1000mi on the car. The biggest issues since I got the car on the road have been a flat tire and a blown fuse. The fuse on the low voltage side of my contactor blew when my 12V battery was low.

I have even been using the $15 Surplus Center 135V vacuum pump without an auxiliary reservoir. It takes 15-30 seconds to pull down to 20in*hg. It comes on quite a bit when I am driving, but maintains vacuum. I think I need to adjust the pressure switch because it seems like the max vacuum the pump can pull is around 20in*hg. I can hear the pump when I first turn on the car, but not after I am driving and the electric motor is running.
 
#42 ·
I got my charger on Ebay. It is a Netgain 3000W charger, but I think it is the same as the Elcon. I wanted to see how much energy it was using and the curve so I hooked it up to a WattsUp power meter. These things are great, but I think there are cheaper meters out there. Here is my charge curve:



The curves look like I expected them to and I'm pretty happy with my $500 purchase.

I have been using about 586WH/mile. Seems high to me, but that takes into consideration all the inefficiencies from the wall to the tires. I typically drive 45-55mph on my daily commute.

My car is running on the sun. I had a solar installation put in last year and right now my production is about 23kwh per day. I was only using about 14kwh/day before I started driving my car. Most days I use between 4 and 10 kwh to charge the car depending on how much I drive so I'm still breaking even.

Based on discharge vs. mileage I think my max range is around 30mi. I have not pushed it much past 20mi though. Most of the time I drive 8-16mi/day.
 
#43 ·
Your build is really nice! I'm working through the idea of converting my e30 and yours is a bit of an inspiration.
I'm curious about a few things -
What kind of acceleration performance you get with your 1000A controller at 156V? Do you ever push max current through your Warp 9? What's your rear differential ratio? What gear do you run the car in most of the time?

Thanks in advance for any response.
-b
 
#44 ·
Your build is really nice! I'm working through the idea of converting my e30 and yours is a bit of an inspiration.
I'm curious about a few things -
What kind of acceleration performance you get with your 1000A controller at 156V? Do you ever push max current through your Warp 9? What's your rear differential ratio? What gear do you run the car in most of the time?

Thanks in advance for any response.
-b
The E30 works great as an electric car except for the brick-like aero.

Right now my current is limited to 400A and ramp up is slow to save my drivetrain. Acceleration is not an issue for everyday driving (0-60 is about 18s). I have not pushed 1000A through the Warp, but I am sure many have. The Logisystems controllers are not very robust and I am pretty sure if I pushed it to 1000A it would burn up. I think I can make it last by keeping the current fairly limited.

I have the 3.73 differential. I start in 2nd and keep the car in 2nd until I reach 50mph. 3rd is good up to 75mph.
 
#45 ·
Last weekend I went to a E30 BMW gathering in Asheville. It was the farthest I have taken my car and at the limit of my range. I charged the car while I was there and was able to make it back home. About 30 or so cars showed up. The car was a hit and quite a few people were very interested.



This inspired me to finally wire up my J1772 receptacle so I can extend my range. I wanted the J1772 receptacle to be rigidly mounted to the car and also keep my NEMA receptacle. I did not have a great spot to put it that was accessible from outside the car so I put it in the trunk. When I am charging with J1772 (very rarely) I will just rest the trunk lid on the cable. I wanted to be able to switch between the J1772 receptacle and the NEMA twist lock. This prevents the second receptacle's leads from being hot while the other is charging. The switch I used is a ON-ON switch that breaks both lines. Looking back I wish I had used an ON-OFF-ON switch, but it really doesn't matter. To turn off the charger I just change the switch position to the other receptacle. I used a 1N4003 diode and 880ohm resistor between pin 4 and ground.

I found these links to be good references for the J1772 wiring:

EVTV
etischer
bruceme good reference, but I really think you should have a switch for connecting/disconnecting your charger



I also got my gauges properly mounted. I took a scrap piece of aluminum I had lying around, used a hole saw to make some 2" holes, bent the ends and wired everything up.



Since my gauges moved out of the radio slot I put a CD player in. Now I have something to listen to on my commute.

 
#47 ·
Hi, thanks for your amazing build thread! This thread is what inspired me to sign up on this forum, since I'm also converting a 1986 325e to electric with a Warp9 motor.

My ride still has the ICE motor (with 398k on the clock:) ) while I gather the rest of the parts I need. Once the old motor comes out, I'll likely start a build thread of my own.

Anyway, thanks for the hard work, your car looks awesome!
 
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