Lessons Learned

Posted June 13, 2010 by rhamje
Categories: The Project Log

Even though I am not completely finished with my conversion, I promised to share the lessons I have learned from it.  There may be more later as I get used to the car, have maintenance and warranty issues, etc.   But for now, my dos and don’ts of EV conversion:

  1. DO Use a high-voltage power pack. You get better range and performance, and it’s safer to work with (less amperage).  The only downside is the cost of having lots of batteries.
  2. DO Use lithium batteries. Better in every way, and they aren’t even more expensive if you plan to drive the car for more than 3-4 years.
  3. DO Use AC drive. Simpler installation, fewer parts, braking regeneration (which works very nicely by the way), better performance.
  4. DO Hire professionals for the work you can’t competently do yourself.  For me this was gasoline engine removal, welding, transmission repair and BMS troubleshooting.
  5. DO Get involved in the EV community, and the one for your make of car.  There are forums everywhere online, full of people in the EV world who are very helpful.  Same goes for the VW Type 3 folks.  But almost any make of car has enthusiasts who can help you.  And they want to help, so ask.
  6. DO Deal locally wherever possible.  I have had the best results working with people in town – the welding folks, mechanics, etc.  And the worst results dealing with anonymous websites far away.  For example, if I’d not been able to drive to my supplier to get the proper batteries (after two mis-shipments), the project would have been delayed at least another month.
  7. DO Buy tools if you need them.  Or rent. Or borrow.   Using the wrong tools is dangerous and yields bad results.  I hurt myself several times because I had the wrong jack, a lousy soldering iron, etc.  If you can’t bring yourself to buy tools, see #4 above.
  8. DO Be prepared for delays and frustrations. When you are making something one-of-a-kind, there will always be problems.  Things take longer than it seems they should, everything costs more than you hope, parts are hard to find or make.  In my case, my five month project has turned out to be most of a year.
  9. DO Get a garage. Working in the driveway has really slowed me down.  I’ve had long delays for bad weather.  I have to put my tools away in the house after every work session.  I was storing large components in the laundry room.  My neighbors’ patience was tested.  The good thing about working outdoors is chatting with all the folks who walk by and wonder what’s going on.
  10. DO Buy reference guides. My Bentley VW manual and the “Convert It” book by Mike Brown have been indispensable.
  1. DON’T Buy a kit. There are no complete kits on the market.  There are really only six main elements in the conversion and you can buy them separately for less (and get the best of each for your job).  The components are: motor and controller; batteries and BMS; charger; DC/DC converter; accelerator POT unit; and transmission adapter.  The minor components such as wire, connectors and relays are easily bought from an electronic supply house like Digikey or Mouser.  Gauges and the switchbox can be bought from an EV or general automotive supplier.
  2. DON’T Pay up front. For major components, use an escrow service like PayPal which pays the vendor when your stuff ships.  Two of my suppliers went out of business on me, one still owing me stuff.  If they won’t accept escrow, break up your bill of materials into small orders and pay each separately with a credit card – at least you can get your money back if they don’t deliver.  I’d suggest no single order of more than $2,000.  If your supplier folds, quickly contact the original manufacturer so they know what happened and can help you with warranty claims.
  3. DON’T Buy things you don’t understand. In my case, the BMS has been the most trouble.  It is far more complicated and sensitive than I expected.  I should have asked other people who had one before I bought it – I might have picked a different system if I had.
  4. DON’T Deal with Electro Automotive. This company is (was) the oldest in the business and has sold thousands of kits for conversions.   But their customer service is atrocious and they may now be out of business.  They don’t sell anything you can’t find elsewhere.
  5. DON’T Use welding cable. With lower voltage DC systems, welding cable is recommended to carry the high amperage.  With a high-voltage system, you don’t need it.  Welding cable is hard to work with, the lugs are difficult to connect to the other components, the wire is bulky and hard to thread through the car, and it’s expensive.  Use 8 gauge insulated wire instead – you can buy it anywhere.  If for some reason I had to rewire my car, I would toss all the welding cable.
  6. DON’T Cut corners on safety. This is a motor vehicle that carries human beings at high speeds.  You don’t want your battery boxes falling out, your flywheel disintegrating, your 12 volt power suddenly failing, you (or your passengers, or your neighbor’s cat) getting shocked, etc.  Insulate all your connections, cover your batteries, tape your tools, use heavy automotive-grade nuts and bolts, get your flywheel balanced, make sure your brakes and suspension are strong enough for the heavier car.  If in doubt, use a bigger bolt, or thicker metal, or fatter wire.  Use lock washers on every bolt.
  7. DON’T Sell your other car too soon. You will be running lots of little errands for this and that.  It’s nice to have your other car for this – sell it once your EV is a daily driver.  I rang up a pretty hefty bill with Zipcar.  But you can’t easily haul your motor or transmission to a shop on a bicycle or the bus.
  8. DON’T Buy a junker car to convert. I’ve been very happy that the car I started with was so nice.  Everything basically worked, the body is in good shape, etc.  Worst would be a donor car with electrical problems.  Converting to electric is hard enough without fighting problems with the basic running gear at the same time.

That’s it for now.  But who knows what the future holds?  Painful and expensive lessons are always lurking in most things in life…

Power play

Posted June 13, 2010 by rhamje
Categories: The Project Log

I gave up on Electro Automotive and purchased a DC/DC converter from another company.  It arrived in just a few days.  On my first attempt to install it, I received a big shock, literally.  After connecting the unit, when I attempted to reconnect the main power a huge arc jumped from the wire to the battery.  I jumped almost as far.  No damage done; just a scare.  When I called the supplier they said, “oh yeah – we forgo0t to tell you about that.  You need thermistors.”  So a couple of thermistors are on the way and I can complete the installation when they get here.

As I understand it, the DC/DC converter wants to draw a huge charge right away to power up its capacitors.  The unit doesn’t have an on/off switch, so the draw happens as soon as power is applied.  Adding thermistors is supposed to help.  These little devices (they cost only $1.38) will absorb the initial draw, converting it to heat.  Instead of a big spark, the thermistors get really hot.  Once the unit is fully powered, the thermistors cool off and everything is normal.

I did all the wiring and installation of the DC/DC converter, leaving two open connections for the thermistors. The box is under the back seat next to the battery.   This is what it looks like:

DC/DC Converter

The battery is to the right.  The connections for this unit are pretty straightforward.  It took me about an hour to get it all done once the sparking issue was figured out.  This is the last major component in my conversion.  All that’s left is buttoning everything up and making it pretty (and getting the darned BMS to work properly).

I have gotten tired of getting little shocks every time I disconnect the main power to work on something.  So I added a service disconnect.  This is two large plastic blocks, called Anderson connectors, that snap together like giant Legos.  I cut the main positive and negative wires in the engine compartment and inserted this connector in between.  Now it’s a tool-less and shock-less process to disconnect everything.

Service Disconnect, Disconnected

Service Disconnect, Ready to Drive

This is a good safety measure also – if the car gets wrecked there is a fairly obvious way to shut off the power.

Basic Statistics on the Conversion

Posted May 24, 2010 by rhamje
Categories: The Project Log

The electric Fastback performs pretty decently.  I was finally able to get it out on the highway and see what it can do.  Top speed on the level is about 60 mph, although I might be able to get a bit more out of it if I pushed really hard.  I haven’t timed a 0-60 acceleration, but it does just fine keeping up with everyone else.

Approximate top speed by gear:

1st = 20 mph with very quick acceleration

2nd = 40 mph with good acceleration up to about 35 mph.  This gear will move the car from a stop at a normal pace.

3rd = 55 mph (maybe more) with decent power.  The car will move from a standing start in 3rd gear, but very slowly until about 20 mph.

4th = 60 mph with very little power (this is a cruising gear with almost no amperage draw, but can’t pull up a hill).

I charged up the car for the first time.  The charger added 28 volts in one hour, which means that a full charge will take a bit less than four hours.  Driving hard on the freeway in “power” mode for 10 miles drew down 32 volts.  From this, I am guessing that the car has about a 30 mile range for high-speed freeway driving.  In-town driving is much easier on the batteries.  I estimate that it can go almost 100 miles on a charge with light acceleration and top speeds under 35 mph.

As promised, I have added up the cost of the conversion.  I’m not 100% finished yet, so there will be a few more small things like carpeting and maybe some more BMS components.  None of this should be very expensive, so this chart is a pretty fair representation.  I separated the items that are not strictly part of the conversion, like new tires.

Pay to: Description Reqrd? Amount
Spirondon Banos Purchase 1973 Fastback Y $2,900
Rife Motors Remove gasoline engine, fix brakes Y $843
EV Components Batteries, BMS Y $9,034
Electro Automotive Conversion Kit Y $10,025
Fab Shop Fabrication work (includes towing) Y $4,432
Integrity Towing Tow to Fab Shop (1st tow) Y $93
Halsey Import Parts Clutch alignment tool Y $2
NAPA Tool for drive shaft attachment Y $7
RechargeCar Safety power disconnect Y $143
Northwest Battery 12v battery Y $76
Gilbertson Machine Balance flywheel and clutch Y $150
Travis Travelstead Consulting on BMS Y $300
EV Parts “Electric” logo Y $9
Oergon Electric Group Wiring 240v AC outlet for charging Y $575
Schucks Auto Supply Misc parts and tools Y $61
Cableties Inc. Cable ties for battery box covers Y $30
Evolve Inc Replacement BMS boards Y $132
Digikey Extra Molex for BMS Y $30
Winks Hardware Misc parts and tools Y $13
TAP Plastics Battery box covers Y $101
Subtotal $28,956
Chuck Volks Werks Regear transaxle N $525
Peter Parker Sale of gasoline engine N -$240
AGS Auto Glass Replace windshield N $300
MotorSpot Radial whitewall tires N $709
Progressive Insurance 6 months full coverage N $1,067
State of Oregon Title and registration N $235
Les Schwab Tire mount and balance N $107
Nationwide Hubcap Chrome trim rings N $51
Subtotal $2,754
State of Oregon Oregon EV Tax Credit (2010 tax year) -$750
IRS Federal EV Tax Credit (2010 tax year) -$2,500
GRAND TOTAL $28,460

As you can see, the total is about $29,000 for the conversion itself before tax credits.  I’ve included title, registration and insurance in the grand total so you can see what they run.   Insurance would be very cheap if not for the special collision coverage amendment that revalues the car to its replacement cost.

My original objectives for the project were: 50 mile range, performance comparable to the original car, no intrusion of the new drivetrain into the trunks or passenger area, stock appearance outside the car, total cost under $30,000, and completion in five months.  Aside from the project taking far longer than I expected, all the other objectives have been met.   “Mission Accomplished”.

Next up: more finishing touches and a “lessons learned” summary.

Pay to: Description Rquired for Conversion? Amount
Spirondon Banos Purchase 1973 Fastback Y $2,900
Rife Motors Remove gasoline engine, fix brakes Y $843
EV Components Batteries, BMS Y $9,034
Electro Automotive Conversion Kit Y $10,025
Fab Shop Fabrication work (includes towing) Y $4,432
Integrity Towing Tow to Fab Shop (1st tow) Y $93
Halsey Import Parts Clutch alignment tool Y $2
NAPA Tool for drive shaft attachment Y $7
RechargeCar Safety power disconnect Y $143
Northwest Battery 12v battery Y $76
Gilbertson Machine Balance flywheel and clutch Y $150
Travis Travelstead Consulting on BMS Y $300
EV Parts “Electric” logo Y $9
Oergon Electric Group Wiring 240v AC outlet for charging Y $575
Schucks Auto Supply Misc parts and tools Y $61
Cableties Inc. Cable ties for battery box covers Y $30
Evolve Inc Replacement BMS boards Y $132
Digikey Extra Molex for BMX Y $30
Winks Hardware Misc parts and tools Y $13
TAP Plastics Battery box covers Y $101
Subtotal $28,956
Chuck Volks Werks Regear transaxle N $525
Peter Parker Purchase of gasoline engine N -$240
AGS Auto Glass Replace windshield N $300
MotorSpot Radial whitewall tires N $709
Progressive Insurance 6 months full coverage N $1,067
State of Oregon Title and registration N $235
Les Schwab Tire mount and balance N $107
Nationwide Hubcap Chrome trim rings N $51
Subtotal $2,754
State of Oregon Oregon EV Tax Credit (2010 tax year) -$750
IRS Federal EV Tx Credit (2010 tax year) -$2,500
GRAND TOTAL $28,460

A Running Car!

Posted May 18, 2010 by rhamje
Categories: The Project Log

There has been major progress this past week and the car is now running properly!

Ten days ago I removed the drivetrain with the motor going to the machine shop for balancing, and the transmission to the shop for repairs.  Gilbertson Machine discovered that both the flywheel and clutch were not balanced.  The flywheel had a bunch of holes drilled in it to make it turn true, and the clutch had some metal soldered on to balance it.  They then reassembled the unit and it purrs like a kitten.  This was worth the $150 it cost.  As I mentioned in my last post, I should have done this earlier.

Chuck’s Volkswerks did the transmission work.  It was re-geared to match the electric drive which has more torque than the old gasoline engine.  First gear remains, what used to be 3rd is now 2nd, the old 4th is now 3rd, and a bigger gear was installed as 4th.  The shop cleaned and painted the whole unit, and also fabricated a plate to cover up the starter hole.  My tape offended his sensibilities, although it was doing the job.  His cover looks much nicer.  The work cost $525 and he even delivered it to my house on Saturday.

Starter hole cover

Finally, the Fab Shop made up some stouter motor mounting spacers for me, and didn’t even charge for it (thanks Dan and Eric!)

On Wednesday and Thursday, Travis formerly of EV Components, came over to help fix the BMS.  We discovered many problems.  Some of the strings of boards were backwards – the positive end must go at the most positive end of each battery bank.  The connectors must be assembled so that specific colored wires are to the left side of the connector housing.  Neither of these things is obvious from the documentation.  Also I had not done a perfect job inserting all the tiny Molex connectors into the plastic housings.  We rewired one bank to the specification and it worked.  I was much relieved.  I have since redone 5 other banks although I’ve not had time to confirm that they work yet.  There are a further three in the back to be rewired, and three in the front – I have ordered parts to complete these.

Travis also figured out how to properly wire the BMS so it will control the charger and motor.  Adding two relays and some more wires allows the BMS to shut off the charger if the batteries are getting too full.  I’m still waiting on an obscure connector to finish this piece.  Some wiring to the existing relays allows the BMS to shut off the motor if the batteries get too low.

So – pending some parts, the BMS is now working and I’ll shortly be able to recharge the battery pack with confidence that no damage will result.

I reinstalled the drivetrain using the new motor mounts, balanced flywheel and clutch, and rebuilt transmission.  The car runs perfectly!  We took it out for a test drive and there is no shaking and no noise.  It goes 35mph in second gear without using all the pedal, and I took it to 45mph in third but couldn’t go faster since I was on a city street.  Next up is to get out on the freeway to see how it does at higher speeds.  But indications are that it will go at least 65mph without difficulty.  The car has been driven 59 miles so far and has more than half its charge left.  None of this has been at highway speeds, nor have we hit any challenging hills.  So its not yet possible to say what the range will be.  But for around-town driving only, I’m guessing it will be 100 miles or more.  We’ll know more as we drive it more.

Remaining items: charger connector, BMS final wiring and testing, battery cover fabrication and installation, DC/DC converter, wiring grommets in a couple spots, spray foam into the various holes, carpet the trunk, make spare keys, and install a heater.  But none of this prevents us from driving the car any time we want!

My next post will recap the cost of the project and what I’ve learned about the car’s performance.  I hope to also report that the last tasks have been completed.

End in sight

Posted May 9, 2010 by rhamje
Categories: The Project Log

Progress has been slow the last couple weeks with some business trips and lack of parts.  I did have the folks at Oregon Electric Group install a 240v outlet on our porch, so now we can easily plug the car in.  I tried it out and no breakers popped!  Auto Glass Solutions NW installed a new windshield and did a beautiful job – it looks exactly like the original only without the cracks and fogging.

We’ve been driving the car a little, but it vibrates pretty badly at about 25mph and will barely shift into fourth gear.  The engine vibrates even when in neutral and with the clutch disengaged.  This makes me suspicious that the flywheel is slightly out of balance.  Electric motors are very smooth and quiet, so any small flaw in the flywheel is very noticeable.  Failure to fix the problem can destroy the motor bearings, so a balanced flywheel is very important.  I had wrongly decided that since the flywheel was working fine on the gasoline engine, it would be fine on the electric one.  Note to other EV converters: when you have your gasoline engine out – GET THE FLYWHEEL BALANCED!

Since I failed to do this when the flywheel was sitting loose in my utility room, now I had to remove the drivetrain.  So – yesterday I did the job.  It took me 3-1/2 hours (not too bad).  On Monday I’ll take the motor to the machine shop for flywheel balancing, the transaxle to the VW transmission shop for repairs to the linkage bushing (which is preventing it from shifting easily), and stop by the Fab Shop to have new motor mount spacers made.  I am suspicious that my current spacers aren’t strong enough, and the front ones are slightly too long (by 1mm).  Since everything is out of the car, I may as well get it all done right.

On Wednesday, Travis formerly from EV Components is coming by to help me complete installation of the BMS.   EV Components sold me the BMS, but they are struggling and all their engineers quit.  Travis is coming to help me as a private consultant, and he’ll probably have it all working in no time.

With luck, I’ll have everything back by Friday and can reinstall the drivetrain next weekend.  With that done, the car will be a daily driver lacking only the DC/DC converter (still no word on that) and some cosmetic things.  And a heater, which can wait now that it’s getting toward summer.

So hopefully my next post will be reporting that the project is essentially finished.  I promise a recap of the final cost, and some basic performance measurements from the working car.

Nearing the Home Stretch

Posted April 12, 2010 by rhamje
Categories: The Project Log

The battery charger arrived this week, after waiting 7-1/2 months.  The car is running, but without a charger I don’t dare drive it far.  So this is a big hump to get over.

The charger is a black metal box 14″ square and 6″ deep, weighing 35 pounds.  The top of it has two fans set amid a field of cooling fins.  The instructions that came with it say to mount it vertically, with the flat horizontal position called “marginal”.   Surely having the cooling fins on top with the fans blowing upwards cannot hurt the unit’s cooling – in fact it should be better than a vertical mount with the fins facing sideways.  So I presume that the “marginal” issue is one of impact shock – there must be circuit boards inside that could crack if you hit a pothole or curb.  Circuit boards are stronger on edge than laying flat.

Long story short – there is no place to mount the charger vertically in the Fastback.  So I had to mount it flat.  To compensate, I added shock mounts.  These are soft-rubber chair leg tips with a hole drilled through the center.  This lets the charger bounce slightly, and should absorb some energy from a hard impact.

The charger fits perfectly where I always intended it to go – inside the former gas tank.

Charger in the gas tank

The cord on the left goes to the wall outlet (more on that later).  The one on the right has three leads: two to the main battery pack (positive and negative) and one small wire to go to the charger interlock relay.  This relay prevents the motor from starting if the charger has AC power – so you don’t drive off while still plugged in.  Unfortunately, the relay that came in my kit has two leads for this function, but the charger only has one.  I have a query out to Electro Automotive about resolving this – we will see if they respond.

Since the charger vents upwards, I made a hole in the trunk liner to compensate.

Trunk liner mod

The charger wants 240V AC power, but it will run on 110V.  Since we don’t have a  240V outlet handy, I made up an extension cord with a 240V plug on one end and 110V on the other.  When I plugged it it, the charger started and went through its startup sequence.  Unfortunately, when it then kicked in to start charging, it popped the breaker in the house.  Thinking, I may have messed up the cord, I reversed the polarity but got the same result.  So, I’ll be calling an electrician on Monday to come install a 240V outlet.  Note to anyone else doing an EV conversion – get a 240V outlet installed on your house if you don’t have one near your parking spot.

Beyond the charger, I was determined to finish off all the other little things that have been undone.  I got a new, smaller 12V accessory battery.

This battery is about 1/3 the size of a standard car battery and weighs a lot less.  Since I don’t need a huge jolt for a starter, this will do the job handily.  Plus it makes space for the DC/DC converter, which has yet to arrive.  This is under the passenger side rear seat.

The other wiring is all finished, except for the BMS.  The guages are connected and all the relays populated.  The relays and BMS are under the driver’s side rear seat and look like this.

Rat's Nest

There is even a USB connector in there, for connecting the controller or BMS to a laptop.  It’s not really as bad as it looks, everything is labeled and documented.  Part of this wiring job were the dashboard guages.  They’re now all connected and the wires taped and tucked away.  With that finished, I glued all the carpet back in place.

Dashboard Wired

A while ago, I mentioned the fusible links in the main battery pack.  Well, today I mounted them permanently with Velcro-style connectors so they won’t accidentally touch something metal.  While I was at it, I took a picture so you can see what one looks like.

A Fusible Link

The car is riding low in the back, so I tried out the airshocks.  Here is a before picture, with the rubber strip on the bumper 17″ from the ground.

Ride Level with Airshocks at 40 psi

I connected my bicycle pump, which read 40 psi.  After six strokes, it was up to 140 psi, and the ride height was 18-1/2″.  This is slightly higher than the original Fastback, reducing the risk of scraping the battery boxes.

Ride Height with the Airshocks at 140 psi

On to some cosmetics.  I put the cabin back together and cleaned it, stripped and painted the engine compartment cover, and gave the car a good washing – its first since August.

Trunk cleaned up

Cabin Cleanup

Last task for this weekend was the “fuel” inlet.  The Fastback has a little door covering the gas cap.  With the pipes removed, there is a 4″ hole  behind this door.  The battery charger plug is only 2″, so I needed to make the gas tank hole smaller, plus shorten the charger wire to suit.  Home Depot to the rescue.  A pair of metal faceplates for electric dryer outlets supply the correct size of hole.  I got some tin snips to cut them into rough circles (they are square).  One plate goes inside, the other outside and they are screwed together.

Big Hole Made Smaller

Then the cord gets threaded through, cut to length, and attached to the weatherproof plug (designed for boats).  With the plug in the hole, the conduit bushing screws onto the back, tightening the entire thing.

Plug in place

So this week will be taken with calling an electrician, going to DMV for license plates (and a new driver’s license while I’m there), putting on the new tires, and nagging Electro Automotive about the charger wiring discrepancy and the still-missing DC/DC converter.  The last task for the weekend was the easiest and most fun – applying the “brag”.

Yes it is!

Woo Hoo!

Posted March 4, 2010 by rhamje
Categories: The Project Log

Today was a real landmark.  The last tweaks were done at the Fab Shop and Rife Motors and I drove the car home!  Under its own power.  As I was driving home a motorcyclist passed me, then slowed and gave me a thumbs up!

Scott at Rife Motors fixed my clutch problem in five minutes.  The cable attachment nut was not on nearly far enough.  He lubed it and then screwed it onto the cable about two inches.  Now the clutch works perfectly.  He refused to take payment for the fix, claiming it was too easy.  Many things are easy if you know what to do.  But still, thank you Scott.

Eric at the Fab Shop fixed the mounts for the last battery box.  He also installed adjustable air shocks to raise the rear end to a normal ride height.   But best of all was how he mounted the valve stem for the shocks.  Take a look:

Air Shock Valve Stem (where the oil filler used to be)

Closeup

Sweet!  Now if the rear is riding low I can roll into a gas station and pump it up.  That’ll be the only time this car will ever go to a gas station!

There is still plenty to do.  I’m still waiting for the charger, so I can only drive about another 20 miles before it will be totally dead.  The BMS is not working right, for some reason I can’t shift into third gear, the interior is a big mess.  But it’s still exciting!  Close enough to taste it now.  So now I harass Electro Automotive for my parts and do some (hopefully) little stuff while I wait.