Porsche 914 EV

This project never seems to get off the ground. I got my new motors and adapter plate along with the new motor controller. I had my friend Chris build an adapter to the adapter. The original was for a Chevy bell-housing, and I have a VW/Porsche 901 transmission. The adapter is pretty much just a ring, and it all fit up nicely. I’m planning to shoot a small video of the new setup and show it getting installed in the vehicle. Unfortunately my plans to do it this weekend are crushed due to a customer calling me to Oxnard and it will require me to head down on Friday and return on Monday…there goes the weekend. I’ve got camping reservations for the Refuel Races at Laguna Seca and I was planning to have a running car, but that looks to be out of the question at this point. Hopefully I’ll still be able to go to the races and watch even if I don’t have a car to drive. Perhaps that will motivate me to get out there every evening and get this thing back on the road.

Just exactly like last year, I had time off from Christmas to New Years and I planned to work on the car, and I was sick the entire time. I looked at all my old post, and its hard to believe it has been a year since I completed all that work. I’m right back looking at the same car as last January. Hopefully this time I’ll get more done before I get busy at my real job. Now that I have all the parts and I’m doing a simpler project, it should be doable. There is a Porsche club meeting in May and also in October that I’d like to take the car to, so lets hope I’m done and able to take it to both.

So I had the week off between Christmas and New Years, and I planned to get a lot of work done on the Porsche. So for the second time I’ve taken time out to work on this project, I got sick during the days I was going to work on it. What a drag. Well, I did go to the store and got an upgrade kit for my welder so that I can MIG weld with gas instead of just the flux core that I have been using for projects around the house. This will make for much better looking welds on the car. I also got a portable sand blaster and some sand to remove some of the rust I’ve found after removing some of the components from the car. I’ll wire wheel it first and then use the sand blaster to get into the corners, and then I also bought some Rust Doctor to neutralize the rust before applying the Rustolium Primer.

I also ordered a tow bar bracket to put on the car for when I need to take it to specialty shops for drive shafts and other items. I also ordered the motor and gearbox “cradle” that I will be modifying to use with my drive-train. The one I ordered is for a Subaru conversion, but it will work really well as a starting point for my conversion. It should save me a lot of time, as well as now I don’t have to build a temporary unit and have a shop custom build off my temp jig.

So even though not much happened on the car itself, I got a lot done in the way of ordering parts and such.

There have been so many changes to the original plan, I thought I’d copy that post and rework it to show the new plan…

Here is what I plan to change about the car:

First of all I’m upgrading the batteries from the 20 US125 lead acid batteries to a battery pack of 100 CALB CA series 100Ah cells. That will take me from 120vdc to about 340vdc. Just the increase in voltage alone should help the car perform better. The controller is remaining and is capable of 400 amps. 550×120=66kw of power, and 400×340 is 136kw. That is a 100% increase in power, but it’s better than that because the CALB cells will hold their voltage better than the lead acid (LA) cells. It is also a change from 242 Ah of which really we can only pull about 100Ah from at the current draws we use in an EV to 100Ah from the CALB battery pack. That makes for about a 100% increase in range for the car. But it should be better than that because I did not even include the fact that I will have less current draw from the pack due to the higher pack voltage, and I’ll also have less current draw from the pack due to the fact that the car is going to lose somewhere between 800 and 1000 lbs during this conversion. (There will be about 590 lbs lost just in battery weight). (67lbsx20 = 1340 lbs – 7.5×100 = 750 lbs) I’ll be able to completely remove the front battery rack and the two saddle racks. I’ll be building a two layer rack that will fill the entire engine bay. I’m hoping that all the cells will fit in this one two layer rack.

Second, I’m putting the car on a diet. I’m removing the steel hood and trunk and the steel bumpers and valences and I’ll be replacing them all with fiberglass parts. This should save about 70 lbs.
FRNT BUMPER STK 17.5 —> F/G FRNT BUMPER 3 = 14.5lbs
REAR BUMPER STK 17.5 —> F/G REAR BUMPER 4.5 = 13lbs
Front Stck Deck Lid 30.5 —> F/G Front Deck Lid 10 = 20.5lbs
Rear Stock Deck Lid 31 —> F/G Rear Deck Lid 10 = 21.bs
Total = 69 lbs. This does not even include any of the valences or rocker panels that are being replaced with fiberglass. I’m going to take detailed notes and document all the weight removal from the car.

Third, I’m installing a new radio. The old one was just awful and if I’m going to be spending any time in the car, I needed a better radio. The radio I bought can stream audio from my iPhone and has handsfree telephone capability. I also will be adding a small 8″ subwoofer to fill in the missing sound that the 4×6 speakers cannot possibly do.

Fourth, I’m installing air conditioning. The car is great in the spring and fall, but the summer heat is not fun. Its well over 100 during the summer and A/C is a must.

Fifth, I’m installing heated seats. Just like the A/C for summer, the car could feel better in the winter if my butt was warmer. Heating the seat is more energy efficient than trying to heat the cabin air. Right now the car has two 1500 watt heaters, and it does do a decent job of heating the air, but thats 3000 watts getting used to heat the air, and not making the car go forward. Heated seats are much less power for greater effect. The hair driers will be replaced with a proper electric heating system as well.

Sixth, I’m installing new headlights and driving lights. I had non functional driving lights in the original bumpers, and I am replacing them with real lights. I am also removing the rotating headlights and all the associated hardware and installing fixed lights into the pods on the fenders of the car. The new lights are much more modern looking and will provide more light with less vehicle weight.

Seventh, I’m installing a new fuse-panel. The original fuse-panel in the Porsche is not very good and uses old style fuses. The new panel uses modern fuses and will be much more reliable. I had problems with a couple of the old fuses not making good contact. I had to clean the fuse and re-install to make the electrons flow.

Eighth, I’m going to go over the entire braking system to insure it is working properly. The parking brake has never worked very well. The handle is hard to pull and the cable seems to bind in the tubes. The parking brake does not always hold very tight. I think it is all in the adjustments, so I’m going to go through the adjustment of the parking brake very carefully. The right front wheel seems to drag more than the others. When the car is on jacks, the other three wheels spin fairly freely, but the right front seems to drag and only gets a short spin. I’m not sure if it is the springs that spread the pads, or if it is the piston that is hanging, but I’m going to go though the setup of the brakes for all wheels very closely to be sure that they can all spin freely. this will greatly reduce the power consumed to drive the car.

Nineth, give the car an alignment. Tires seem to wear quite evenly on this car, but a proper alignment should make the car roll smoother and give a little bit better range.

Tenth, the car is getting a new trans-axle. I purchased a BorgWarner 31-03 single speed gearbox that will mate to the new Siemens motor and be controlled by the new AzureDynamics DMOC645 controller. The controller will be commanded by the yet unobtainable (but soon) GEVCU (Generalized Electric Vehicle Control Unit). There will be some sheet metal removal in order to fit the new transmission, which will eliminate more weight, and the transmission is FAR more efficient which should help get more range. In order to get the gearbox to work, I have to have custom axles fabricated. Should not be too hard, but it is custom. That and the custom firewall I have to fabricate in order to install the motor and gearbox are now the most challenging part of this project. Originally it was going to the installation of the A/C system.

So there is the project in a nutshell. I have many of the parts already here, and I’m just waiting on some others to get started. What started as a simple battery upgrade has evolved into a pretty big project. Just building new battery racks and installing them to my existing system would have been too easy. Now I’ve got more batteries, new motor, new gearbox, new axles, and all the other projects.

It looks like I typed them in no particular order…
1 – New Batteries (100, CALB 100Ah)
2 – Weight reduction (fiberglass body parts)
3 – New Radio
4 – Air Conditioning and Heating systems.
5 – Heated seats
6 – New Headlights and driving lights and turn signals.
7 – New fuse panel
8 – Rebuild entire braking system, including the parking brake mechanism.
9 – Alignment
10 – New motor and gearbox.

There are lots of other small items that are really subcategories, so I’ll document them as I complete these major items.

Settling back in after the honeymoon took longer than anticipated. Who knew it would take so long to open gifts and write thank-you notes. The generosity from everyone was overwhelming. Thank you all for everything.

Now on to the EV update. I had done a quick layout of the batteries once they arrived and I confirmed the dimensions, but I kept ignoring the height. I knew these were taller, but I also knew that I was using some thin interconnects and did not think the extra height would be a problem. I thought wrong. Once I started detailing the layout and included height, I found that I needed about an inch (perhaps 3/4″) more height. The rack is constrained between the motor and the engine lid, so there was not even an inch to spare.

Plan B is perhaps a better way to go. I’m building three separate enclosures in the engine compartment. One on each side of the motor and one smaller one on top of the motor and the other two enclosures. By moving the cells alongside the motor I’ll be lowering the center of gravity which should help handling. The top cells will now be laying on their side which also lowers the cg for them as well. The same problem existed in the front batter box, so I’m moving it from the old gas tank compartment to the front trunk. this will lower the rack a few inches and move the weight forward, both of which should help to balance the car and lower the cg.

Moving the battery box to the front compartment also means that I’ll have to redesign the layout of the air conditioning system. I was going to build a system similar to what renegade hybrids does for 914 v8 radiator systems. It is a good setup, but does take up the entire front trunk. My new system will be similar to the way the factory did the A/C by cutting a hole in the floor of the trunk. I’ll be building a floor to capture the air between and force it through the condenser.

Now that the design has been redone, its time to get fabricating. I think I’ll start with the A/C system since it is going to go below the battery racks, and that will also force me to finish installing the system in the cabin. Right now it is just hanging by a few screws.

It has been an extremely busy year for me at work, and with my upcoming wedding, I’ve had little time to even think about the car let alone work on it. I knew when the batteries did not arrive as they were supposed to in September last year, I was going to have trouble working on the car. My slow period at work is from late september to about March, and when the batteries arrived after the new year, I knew I’d have trouble getting it done before I got busy. I also had a pool-house to build, and that project took priority over the Porsche last spring, so no progress on the Porsche. The pool-house is complete, I’m starting to slow down at work now, but nothing is going to happen until after the wedding and honeymoon, which we return from on Halloween. Hopefully I’ll have a productive November and December and have the car back on the road somewhere near New Years Eve. Look for postings to resume in November and I return to this project. It’s hard to believe the car has been down for so long. The other two times the batteries needed replacement, I think I let it sit for about 4-6 months and then the battery installation took only one day and it was back running. This years project is for more substantial as I’m upgrading nearly everything on the car, but still….Its been down since January 2010 and I pulled the batteries out in July 2010 when I ordered the Thundersky batteries. That means it will have been down 2 years once I get it going again.