Wednesday, January 23, 2013

Exciting Day and a New Challenge

It’s an exciting day today!  I've passed 5,000 pageviews on my blog (5,146 to be exact).  That means if I’d let Google put ads on there they would have paid me about $1 so far!  I also found out I've been working on the car so long that the people at Ace Hardware know me by name.  I'm not sure that's a good thing.  More interesting though is that the place I work for just announced they’ll have their third “Bring Your Ride to Work” day 4 weeks from today.  I've dreamed about bringing a vehicle in since the 1st annual BYRTW day (which was about 6 years ago), but always ran into problems actually getting my vehicle in to work.  The first year I was planning to take my 64 CJ6 in but a nut stripped out inside the transfer case 100 feet from my house the day of the event.  The second time I planned to bring in the CJ again after finishing the power steering conversion on it, but the steering wobble I was trying to correct with the conversion reappeared 5 days prior to the event.  So now I’m faced with a new challenge: getting my Porsche roadworthy in less than 28 days!  Here’s what I’m up against.  We’ll start with stuff I've recently finished.

Months ago I completely took apart the interior with the intent of restoring the dashboard.  Well, I got the dash 98% complete and never finished it off or put anything together.  Two days ago I decided it was time to put it all back, and amazingly it only took 4-5 hours to do!  And it looks fantastic with the new dash in place.  What the heck was I waiting for?!  Now all I’m missing is the passenger seat.  Sorry, no pics...

Another outstanding part of the system is the vacuum needed to work the brake booster.  For those of you that don’t know, a normal gas engine provides vacuum when it sucks air into the intake.  Historically, this vacuum has been used for all sorts of things like emissions control, crankcase ventilation, cruise control, wiper blade operation, and of course, brake assist.  Since the engine is long gone, I need a dedicated pump.  A lot of EVers use a piston pump because they must be already commercially available.  My friend, Joe, has one of these on his car and the only gripe about it is it’s so dang loud!  In fact, it’s the loudest thing on the whole car. 

By chance, I ran across a rotary vane pump on that may do the trick.  The benefit of a rotary vane pump is they tend to be quieter.  After finding the product data sheet on it, it appears to have very similar characteristics to Joe’s piston pump, so I’m gonna give it a try.  I also found an automotive fan motor in there and a jaw coupling for a grand total of about $50 (which is about $200 less than any piston pumps I've found) that I just need to mount together.  And here it is!

Now I get to find out if this $50 was a waste or not.   I hooked it up to the brake booster and let it run for a few seconds before pumping the brake pedal.  And it’s definitely working!  After turning it off, I can tell the force to push the pedal is going up after 2 pumps or so.  Only problem is I’m not sure it’s any quieter than Joe’s is.  But luckily when I’m showing it off to Joe, by chance we figure out that if you baffle the inlet it’s actually super quiet!  Win win.

Okay, so here’s what I have left to do:
-      Mount the vacuum pump
-      Mount the coolant pump
-      Mount the coolant reservoir
-      Mount the coolant heat exchanger (heater core)
-      Plumb the coolant lines
-      Finish the battery racks
-      Adjust the motor coupler
-      Order batteries
-      Do a heck of a lot of wiring
-      New tires
-      Alignment
-      Get Insurance and temp registration
-      Complete the charger

Doh!  The charger is not mature at all.  In fact, it’s still in schematic mode.  That’s certainly going to be the long pull, but luckily I have a backup plan.  Joe has a mini-charger that I can use.  It’d be a huge pain to recharge since I’d probably have to disassemble the whole battery pack, but that may be my only option.

Well, what am I doing here wasting time on the computer?  I’d better get out there and start working!  Only 27 days left and a lot to do!

Friday, January 11, 2013

That's where it's all gonna go

Ok, maybe not everything, but I got a lot of stuff to fit under the hood.  Lots of tangible progress since the last post.  The next two pics are of the entire engine compartment.  You can see the motor controller on the left, the potentiometer in the front, the DC-DC converter on the firewall, and the water coolant tank up front as well.  Ok, that coolant tank isn't actually mounted yet, but its got a home.

I made a mount for the vacuum tank, but when I got the controller in I realized they ran into each other.  Not a big deal to move it but whoops!  I'm also not sure I'll need a tank.  After hearing Joe's noisy piston vacuum pump I've decided to try and make a rotary vane pump work.  It's also relatively cheap, but we'll see...vacuum tank, if I use it, is that big black PVC tube.

Here you can see both of my contactors.  They connect and disconnect the battery pack from the motor and controller and are two stages of safety in case I need to disconnect quick for some reason.  you can also see where the big cables are going to hook up to the controller.

Here is the converter that takes the 225v from the main battery pack and steps it down to 12v to operate all the regular stuff in the car.

Here is the potentiometer that tells the controller how hard I'm pushing down on the pedal.  Everything is hooked up and calibrated, I just need to weld one bracket in place that's currently held on with a clamp.

And here's my first clamp casualty.  Normally I clamp parts together, then tack weld them (very small welds just to hold the pieces together), then take the clamp off and do the rest of the welding.  Well this time I figured it was such a small weld I'd just do it with the clamp in place.  When I went to take the clamp off I noticed there was a puddle of liquid metal on one end.  I think these are made of tin or aluminum.  Oh well!