The Zilla's Radiator

I mounted the small radiator that will be used to dissipate heat from the Zilla controller. It may be a bit difficult to see what's what in that picture. It's a black radiator with the car's black condenser serving as the back drop, with a little bit more black thrown in here and there for good measure.



I'll be routing the coolant tubing from those white inlets up to the passenger side next to the firewall, were all the electronics will live. I'm also thinking that I might put some ducting in that will help to pull air through it. The fan that blows air into the motor has to such that air from somewhere, why not through that little radiator? My only concern is wet conditions. I don't want to suck any moisture into the fan, not blow it into the motor. I'll think on it a bit more.

Painting Work is Done

I pulled all of the masking tape and paper out of the engine bay this morning and paint work turned out great. No over spray and a good clean surface on each. The paint doesn't match perfectly in the engine bay because the original paint was subjected to 9 years of oil and road grime, but it looks good enough to me. Check it out:




I fit a few of the parts together to figure out how I'm going to mount the AC compressor. After a couple hours of work, I think I've got it sorted. I made a cardboard template for the base plate and fabricated a small piece of angle iron that should work out as a top bracket. Now I just have to see about having that metal cut up properly. A plasma cutter is what's in order.

Masking Up

This morning I discovered a black hole of time under the hood of the car. It took me more hours than I thought conceivable to mask the engine bay off in preparation for paining.


This is the right or passenger side...


and here is the left, or drivers side. Like they say, put the time in masking properly before you paint and you'll be that much happier with the end result. If that's true, then I should be apoplectic with joy once I peel it all off. I've already primed the pieces, so tomorrow, I'll paint. I figured that I'd paint everything that's permanently affixed to the car red (BMW 314 red), and everything I bolt to the car will be black.

Paint Prep

After a week spent in cool San Francisco, I'm back in the desert heat and ready to resume work on the car.

Today I worked on getting all the proper holes drilled in the support structure for the battery trays so that I can anchor them down properly. Then I worked on cleaning all the new steel off, as well as all the body work nearby so that I can mask it up and begin paint work. Not all together exciting, but necessary if I want to keep it all from rusting away and looking bad.

Later I'll start masking it all up and I'll post a picture or two for all to enjoy.

It looks like the soonest I can expect the batteries is going to be mid October. Later than I would have liked, but that's how it goes. It will give me time to finish just about everything else before they arrive. With some hard, smart work, I'm hoping I'll be able to build the cables, drop them in and be ready to go shortly after they show up.

Back Component Box

Pictured above is the box in the trunk with three of the cars components in it. The charger on the right, and two DC to DC converters. None of it is wired up yet, or even bolted in for that matter. This is just a dry fit test. Though you can't see it, there's a cord that runs out of the back of the box on the charger's side. That runs to the fuel door on the passenger side of the car. One of those cables you see will be routed back to connect to that. The other cable will be connected to the batteries in the box that you can barely see at the very bottom of the picture.

Also on that side is a 2" tube ducted into the box to provide fresh air to the charger when it's operating. The charger has two fans in the back that vent air out the front into what will be the interior of the trunk. I need to make sure fresh air can get to those fans, and that stale air has a way out (that vent will be elsewhere). Once I've put some paint on the steel I cut to make room for that, I'll be ready to bolt it all into place.

The DC to DC converters will be wired in parallel and will put out the 12 volts needed for the car's normal electric systems, and about 80 amps continuous, 100 amps peak.

Battery Support Part V

This may be the last post were the focus is battery support. Today my friend Tim and I welded up what should be the last of the bracing to support the battery trays. With the choice of the newer lighter batteries, I'm confident that the bracing is more than up to the task.


Here you see the cross bracing we put together on the passenger side of the car. The other side is similar.


This is a shot of the new trays I built out of 14 gauge steel. All in all, it saved 15 lbs of weight swapping the heavier ones out. With the batteries being lighter than the lead acid I'd planned, I no longer need the trays themselves to be a structural support, they just need to hold the boxes in position. You'll notice that the box in the back is smaller than the tray. Well that's the one I mentioned I was going to have to have redone. You can see the size of the footprint the box will take up has grown a bit.


I'm leaving the heavier tray at the very front because the power steering pump will be suspended from that one. It's going to need the strength.


Last is a shot of all the boxes in place. I haven't secured the trays down to their moorings just yet; I'll be doing that tomorrow. There's only a few more mechanical items to sort out now; mounting the blower fan for the motor, the vacuum pump for the brakes and the compressor for the A/C system. The compressor is going to be a challenge. It may not be running when the car hits the road, but it will need to be working before next summer.

Odds & Ends Part V

Well, it's been a very busy week and today was the first chance I've had to work on the Z3. Let's tally up what I did, shall we?

1. Finished the mount for the box that's going in the trunk. It will fit through the hole I've cut and into the cavity that was occupied by the fuel tank. Luckily, there was a mounting bracket welded to the chassis in very nearly the perfect spot for use to support the box. I cut a piece of light steel to bolt to it, and the box will simply rest on it, kind of wedged into place. I'll clamp it down on the front edge, and that will prevent it from moving at all.

2. I also cut a 2 inch hole in the back of the box. I will connect some ducting to it and it will do one, possibly two things. It will provide fresh air to the fans of the charger while it is running, and it may also be the conduit for the AC power line to the charger. I might just drill a separate hole for that so there is nothing in the tube obstructing air flow.

3. I figured out how I'm going to mount the power steering pump. I had decided that I would simply suspend it from the front battery box making use of the room there. Today I cut and fitted all the steel needed to support it. Next up for that is simply weld the steel up and then drill out a few holes so that I can mount it in place, easily removing it if necessary.

4. One of the biggest pieces of news this week is I've opted to scrap the idea of lead acid batteries in favor of Sky Energy LiFePo4 batteries. I'd come across a fabulous series of videos put together by a gentleman by the name of Jack Rickard, in which he talks about how best to treat LiFePo4 batteries. All fascinating stuff, but what really caught my attention was the price he mentioned that he paid for the batteries. When I started looking into the project a year and a half ago, a similar pack of Thunder Sky's would have run me over $20,000. Well they've come down substantially, making them much more economically viable. Jack was kind enough to answer some of my questions, and encourage me along. If you care to check out his project, you can see it here. First rate stuff!

The Sky Energy's will weigh in at 475 lbs, versus the 737 lbs that the lead acid I had intended to use would have weighed. In addition, if handled properly, they are rated to handle 3000 charge/discharge cycles. That amounts to approximately 150,000 miles, or for all practical purposes, the life of the car.

5. To that end, I need to redesign one of the battery boxes and the tray that holds it to accommodate the different shape of the batteries. Fortunately, there is no need to adjust any of the bracing that we'd welded up over the past few weeks. However, I will be able to reduce the weight of two of the trays used to hold the battery boxes. The two trays weigh in at about 32 lbs, and I should be able to drop that to about 10. Today I took all the necessary measurements and began cutting up the new lighter steel to hold it all.

That's all for now. Hopefully next week, I'll have more time for the project.