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 42 Thundersky 160Ah cells. That will take me from 120vdc to about 144vdc. Just the increase in voltage alone should help the car perform better. The controller is remaining and is capable of 550 amps. 550×120=66kw of power, and 550×144 is 79.2kw. That is a 20% increase in power, but it’s better than that because the Thundersky cells (TS) 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 160Ah from the TS battery pack. That makes for at least a 50-60% 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 823 lbs lost just in battery weight). (67lbsx20 = 1340 lbs – 12.3×42 = 516.6 lbs) I’ll be able to completely remove one of the battery racks, and possibly the two saddle racks, if I don’t want to keep them as storage bins. I’ll be modifying or replacing all the battery racks in an effort to get them to work better with the new batteries and to remove any unnecessary weight.
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. The other item I might do is to lighten the flywheel. I understand that for every pound you remove you remove a virtual 50-100 pounds of car weight in first gear. See this link. http://www.uucmotorwerks.com/flywheel/how_a_lightweight_flywheel_work…
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.
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 reinstall 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.
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. Most of all I am waiting for the batteries to arrive. I ordered them in August, and I am still waiting. Last word I got from Richard at Alliance Renewable Energy was that they should be arriving to the port in the last week of December and will take a week or two to clear customs. I emailed him this morning to get an update, but I have not received a reply just yet. What started as a simple battery upgrade has evolved into a pretty big project.