stopcrazypp
Well-Known Member
Very nice car. ditto on the request for more pictures. Especially under the rear hood.
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Daniel's EVPorsche 911 conversion
- Thread starter daniel
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Very nice car. ditto on the request for more pictures. Especially under the rear hood.
I can't do a walk-around video right now because I moved the Porsche into the garage. (They told me I'd get the charging cable Monday) I'll try to do that later. I always have problems with those photo-sharing sites. But I've attached here two pictures of the second charger in front, and three of the innards in back. The same pictures plus one other show up better on this thread over at PriusChat.
There are two chargers for fast charging, even though I had said I actually preferred slow charging, which would not have required me to have a high-amperage circuit installed to the garage.
Because of all the batteries, Paul had told me I'd either have to:
1. Put the charger in front and the spare tire in the back seat, or
2. Put the charger in the back seat, giving up the back seat permanently, and the spare tire in the front, or
3. Leave the spare out of the car and put the charger in the front, or
4. Leave the second charger in the garage, carry the spare in the front, and plug in several cables for the second charger every time I charge the car.
I did not want to give up the back seat, or drive without a spare, so that left me with option 4. I took the charger out and moved the spare from the back seat, where it had been for shipping, to the front trunk, only to discover that it would not fit! I got into the back seat, and discovered that nobody but a contortionist could possibly ride back there, and I very nearly was unable to get out. So I got the spare back into the back, in such a way that one back seat is still open, in case I ever have occasion to offer a ride to a contortionist, and I put the charger back into the front. The upside is that for charging I'll only have to plug in the one power cable, like a normal EV. I lose half my back seat, but that's not as bad as I had thought, when I imagined a human being could actually sit back there.
There are two chargers for fast charging, even though I had said I actually preferred slow charging, which would not have required me to have a high-amperage circuit installed to the garage.
Because of all the batteries, Paul had told me I'd either have to:
1. Put the charger in front and the spare tire in the back seat, or
2. Put the charger in the back seat, giving up the back seat permanently, and the spare tire in the front, or
3. Leave the spare out of the car and put the charger in the front, or
4. Leave the second charger in the garage, carry the spare in the front, and plug in several cables for the second charger every time I charge the car.
I did not want to give up the back seat, or drive without a spare, so that left me with option 4. I took the charger out and moved the spare from the back seat, where it had been for shipping, to the front trunk, only to discover that it would not fit! I got into the back seat, and discovered that nobody but a contortionist could possibly ride back there, and I very nearly was unable to get out. So I got the spare back into the back, in such a way that one back seat is still open, in case I ever have occasion to offer a ride to a contortionist, and I put the charger back into the front. The upside is that for charging I'll only have to plug in the one power cable, like a normal EV. I lose half my back seat, but that's not as bad as I had thought, when I imagined a human being could actually sit back there.
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I'm really the wrong person to ask about that. Maybe the biggest difference is that I have mine, and I can drive it now (for maybe another 20 or 30 miles, until the charging cable arrives). Can you buy the RUF Porsche yet? If not, that's a pretty big difference. But as for technical or quality differences, I cannot even tell you much about mine, and I know nothing about that other one.
I'm always happy to see more EVs available, but pretty tired of promises of EVs that are "just around the corner."
ZapX
Obvio
RUF
Aptera (I think there's hope for them)
Zenn City Car with the Eestor ultra-caps
and all those cars from big companies that are just two years away, and have been for half a decade...
That's what's so great about the Roadster. Even though there's a years-long waiting list, at least they're building them and putting them in people's hands. And all the little conversion shops like Paul's, which are micro-volume, but are putting cars on the road, and even poor maligned (sometimes with good reason) Zap, who for all the criticism is putting EVs on the road, even if they're slow and short range. They are excellent for some uses.
JRP3
Hyperactive Member
I doubt it. Most likely when they were using the Zilla controller they could have a 225+ pack voltage and the controller could step it down to something like 172 which the motor can easily handle. With the higher pack voltage and lower motor voltage you don't feel any effects of battery voltage sag. I've never seen a system that steps up the voltage. From the picture it looks as if they are not using the Zillas any longer, (maybe a Logisystem or Electrocraft?), since they aren't being made, and the controller they are using isn't capable of running the higher voltage. I hope you got a price break for the lower voltage system.
No price break. I paid in advance what was stated in the original contract. I do not know if the parts used were equivalent to the ones originally planned. The contract says 1,000-amp controller, but does not specify a brand or model. I believe the batteries are the same as originally planned, because there's no way he could have expected to put twice as many in. There's just no way they would have fit. There's hardly room for the ones it has.
Tomorrow I plan on taking a short jaunt on the freeway to log amperage vs speed. I still have 75 percent SoC. I'll post my results.
They're telling me I'll get the charging cable Monday.
Daniel
Tomorrow I plan on taking a short jaunt on the freeway to log amperage vs speed. I still have 75 percent SoC. I'll post my results.
They're telling me I'll get the charging cable Monday.
Daniel
Random comments:
* Yes, the Zilla is basically out of production, and the alternatives tend to not be as powerful.
* Unlikely that they would step up your voltage. Yes, the Prius does that, but I don't think that technology is readily found in EV conversions.
* It probably doesn't perform as well as their higher voltage Zilla based prototypes had, but it sounds like you are a perfect customer for them - someone who isn't super concerned about performance.
* It looks like they drive the stock power steering pump and AC compressor off of belts coming off of the drive motor. Since EVs tend not to idle (the motor just stops) I wonder if your AC works when the car is not in motion?
* I hope there is some kind of battery management system in there keeping the different cells balanced over time.
* Yes, the Zilla is basically out of production, and the alternatives tend to not be as powerful.
* Unlikely that they would step up your voltage. Yes, the Prius does that, but I don't think that technology is readily found in EV conversions.
* It probably doesn't perform as well as their higher voltage Zilla based prototypes had, but it sounds like you are a perfect customer for them - someone who isn't super concerned about performance.
* It looks like they drive the stock power steering pump and AC compressor off of belts coming off of the drive motor. Since EVs tend not to idle (the motor just stops) I wonder if your AC works when the car is not in motion?
* I hope there is some kind of battery management system in there keeping the different cells balanced over time.
JRP3
Hyperactive Member
Maybe you could take a closeup of the motor controller or tell us what it says on it, I thought I could make out a label in one of the pictures. There are a few controllers that claim 1000 amps. They could have run higher voltage by using more, smaller batteries. Higher voltage gives better efficiency and more power. Unfortunately it's looking as if you didn't actually receive what was promised or paid for.
Some sort of cell balancing is important to avoid over or under volting a cell which can cause damage. Don't take the SOC too low until you know the pack is balanced or you can monitor each cell voltage.
Some sort of cell balancing is important to avoid over or under volting a cell which can cause damage. Don't take the SOC too low until you know the pack is balanced or you can monitor each cell voltage.
The power steering and A/C compressor are indeed operated from the motor. And as you presumed, do not work when the car is stationary. However, either can be operated by putting the transmission into neutral and giving it some pedal. Spokane does not get very hot. On the hottest days, on the freeway with the windows closed, I would use the A/C. But in town, driving slowly, I'd be more likely to have the windows open. And if I was using the A/C, the car would not warm up much during the brief times I'm stopped at a light. If I got stuck waiting for a train I could always put the car in neutral and run the motor enough to get some compressor. The Prius does it better, using an electric compressor, but it was designed from the ground up for what it does. Turning the steering wheel while stopped is very hard. But with a little motion it's not a problem, and I can get power steering back the same way as the A/C, by giving it some pedal in neutral.
The chargers have integrated BMS built-in. I cannot monitor individual cells, but the BMS does, and I've been told it provides the balancing. The battery importer assures me I can go down to 20% SoC. Lithium can safely go much lower than lead.
I will take a close-up of the controller if you can tell me which thing is the controller. I have no idea. Either describe it from my picture, or take my picture and edit an arrow onto it.
I plan on taking a short jaunt onto the freeway today, since I am at 75% SoC now and expecting the charger cable to come tomorrow. I'll log amperage vs speed, and estimate my range. If it is significantly less than is stated in the contract, I'll be concerned. I'll also try to time my zero to 60 time, and if it's more than the Prius I'll be concerned. That might have to wait until I have someone with me, though. The contract does not state a zero to sixty time. I have merely his verbal statement that it should be around 6 to 8 seconds. That was not stated as a promise. But if it's 12 or 15 seconds, then he misrepresented it. However, it would be extremely unfair to speculate that he misrepresented until I actually have some numbers. At this point I only have the subjective impression that it's not going as far or as fast as I had expected. And while I've been driving electric for two years, and know something of electric driving, I've only driven this car a few miles and don't yet have the feel of the most efficient use of the transmission, and admittedly I've been lead-footing.
Daniel
The chargers have integrated BMS built-in. I cannot monitor individual cells, but the BMS does, and I've been told it provides the balancing. The battery importer assures me I can go down to 20% SoC. Lithium can safely go much lower than lead.
I will take a close-up of the controller if you can tell me which thing is the controller. I have no idea. Either describe it from my picture, or take my picture and edit an arrow onto it.
I plan on taking a short jaunt onto the freeway today, since I am at 75% SoC now and expecting the charger cable to come tomorrow. I'll log amperage vs speed, and estimate my range. If it is significantly less than is stated in the contract, I'll be concerned. I'll also try to time my zero to 60 time, and if it's more than the Prius I'll be concerned. That might have to wait until I have someone with me, though. The contract does not state a zero to sixty time. I have merely his verbal statement that it should be around 6 to 8 seconds. That was not stated as a promise. But if it's 12 or 15 seconds, then he misrepresented it. However, it would be extremely unfair to speculate that he misrepresented until I actually have some numbers. At this point I only have the subjective impression that it's not going as far or as fast as I had expected. And while I've been driving electric for two years, and know something of electric driving, I've only driven this car a few miles and don't yet have the feel of the most efficient use of the transmission, and admittedly I've been lead-footing.
Daniel
JRP3
Hyperactive Member
It looks as if the controller is the aluminum box to the right, with what appears to be blue lettering on it. I can tell that your acceleration at 144 volts will be significantly less than at 200+
Looking at the pictures of the rear compartment I am guessing the following:
Lower left: Air vacuum pump for power brake booster. (Rather oversized by the looks)
Upper left: Rear charger. (Looks heavy)
Middle bottom: Pulley from the rear of the electric motor.
Middle top: Power steering pump on the left, A/C compressor on the right.
Right: Iota DLS-45 144->12VDC for accessories.
I don't see the motor controller there. Maybe it is under the rear seat?
Lower left: Air vacuum pump for power brake booster. (Rather oversized by the looks)
Upper left: Rear charger. (Looks heavy)
Middle bottom: Pulley from the rear of the electric motor.
Middle top: Power steering pump on the left, A/C compressor on the right.
Right: Iota DLS-45 144->12VDC for accessories.
I don't see the motor controller there. Maybe it is under the rear seat?
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Logisystems make a popular DC motor controller alternative to the Zilla. (Although 1000amp instead of 2000amp).
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JRP3
Hyperactive Member
Better not be with a series motor running that voltage. Regen doesn't work too well on advanced brushes, since they become retarded on regen.
Here's a picture of the thingy on the right. Apparently it's the voltage converter that makes 12 volts from 144 volts for the car's 12-v stuff. I've flipped the picture to make it easier to read the writing.
No regen. That is correct. Paul convinced me that regen doesn't do enough good.
Very preliminary numbers. VERY preliminary. Once I have the charging cable (which they said would come Monday, which probably means late afternoon / early evening Monday) I will make some more careful tests including some longer drives. But today I took it on the freeway for a bit. The amperage jumps around a lot with terrain changes and with small differences in pedal pressure. But it seemed to draw about 150 amps at 50 mph, 200 amps at 65 mph, and back off the freeway on a surface through street, it seemed to draw about 50 amps at 35 mph. My pack holds 200 amp-hours. This gives a range of 65 miles to dead empty, or 52 miles to 20% DoD, which the battery importer told me is safe for these batteries.
The e-meter (which Paul set to 100 a-h for some odd reason) said 47.4% when I started and 11.1% when I finished my 11.9-mile trip. About a mile to the freeway, then a ways on the freeway, then home on the surface street. Since my pack is twice the size of what the meter thinks, I actually used 18% of my energy, which works out to a total range of 65 miles to empty.
I visited a friend and drove very gently home afterwards. 2.2 miles and I used 6.5 a-h. Again, that works out to about 67 miles range.
This is very discouraging. It suggests that I'm getting about 2 1/3 miles per kWh (my pack is 28 kWh). My Zap Xebra gets 3 miles per kWh measured at the wall. But it's much lighter.
Maybe I just need to learn to drive it better. But if Paul really thought I was going to get 125 miles on 28 kWh then he was assuming almost 4.5 miles per kWh.
Can anybody tell me how many miles per kWh you'd expect to get from a converted Porsche? Paul did say it would improve as the motor breaks in. He said the bearings are tight when new and that causes more friction than after it's broken in. But he didn't tell me how much of an improvement I should expect. Do you folks agree that the motor will improve, and by how much?
No regen. That is correct. Paul convinced me that regen doesn't do enough good.
Very preliminary numbers. VERY preliminary. Once I have the charging cable (which they said would come Monday, which probably means late afternoon / early evening Monday) I will make some more careful tests including some longer drives. But today I took it on the freeway for a bit. The amperage jumps around a lot with terrain changes and with small differences in pedal pressure. But it seemed to draw about 150 amps at 50 mph, 200 amps at 65 mph, and back off the freeway on a surface through street, it seemed to draw about 50 amps at 35 mph. My pack holds 200 amp-hours. This gives a range of 65 miles to dead empty, or 52 miles to 20% DoD, which the battery importer told me is safe for these batteries.
The e-meter (which Paul set to 100 a-h for some odd reason) said 47.4% when I started and 11.1% when I finished my 11.9-mile trip. About a mile to the freeway, then a ways on the freeway, then home on the surface street. Since my pack is twice the size of what the meter thinks, I actually used 18% of my energy, which works out to a total range of 65 miles to empty.
I visited a friend and drove very gently home afterwards. 2.2 miles and I used 6.5 a-h. Again, that works out to about 67 miles range.
This is very discouraging. It suggests that I'm getting about 2 1/3 miles per kWh (my pack is 28 kWh). My Zap Xebra gets 3 miles per kWh measured at the wall. But it's much lighter.
Maybe I just need to learn to drive it better. But if Paul really thought I was going to get 125 miles on 28 kWh then he was assuming almost 4.5 miles per kWh.
Can anybody tell me how many miles per kWh you'd expect to get from a converted Porsche? Paul did say it would improve as the motor breaks in. He said the bearings are tight when new and that causes more friction than after it's broken in. But he didn't tell me how much of an improvement I should expect. Do you folks agree that the motor will improve, and by how much?
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OK, so that gets you 12V from the traction battery.
Iota DLS-45 12 volt 45 amp regulated battery charger
So, I still don't know what is the motor controller. Is the black box on the left a charger or a motor controller?
Iota DLS-45 12 volt 45 amp regulated battery charger
So, I still don't know what is the motor controller. Is the black box on the left a charger or a motor controller?
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JRP3
Hyperactive Member
EV's are usually rated by watt hours per mile, wh/mi. I consider a good EV to be about 250 wh/mi. and a poor one to be 500 wh/mi. If your 28Kw pack is giving you 67 miles of range you're using about 420 wh/mi, not great, but a lot depends on driving habits and terrain. Also air up your tires as much as is comfortable, and as much as they can safely handle.
From what I know about LiFePo4 batteries it takes a few cycles to get the full amp hour rating from them so they should improve a bit. As for the motor, I'm not sure about tight bearings, though I guess it's possible, but I do know that the brushes will probably seat more and the commutator will get a burnished patina which will improve efficiency.
If you were told to expect 125 miles of range out of 28Kw you'd have to be averaging less than 220 wh/mi since you can't use every drop of energy. I doubt your car could do that, unless you were doing maybe 30 mph the whole time. You might do a search through the EV album and see if there are other cars like yours and what their wh/mi is. http://www.evalbum.com
The motor controller will probably be mounted pretty close to the motor, so it may be somewhat buried. Did you get any literature for the components in the vehicle?
From what I know about LiFePo4 batteries it takes a few cycles to get the full amp hour rating from them so they should improve a bit. As for the motor, I'm not sure about tight bearings, though I guess it's possible, but I do know that the brushes will probably seat more and the commutator will get a burnished patina which will improve efficiency.
If you were told to expect 125 miles of range out of 28Kw you'd have to be averaging less than 220 wh/mi since you can't use every drop of energy. I doubt your car could do that, unless you were doing maybe 30 mph the whole time. You might do a search through the EV album and see if there are other cars like yours and what their wh/mi is. http://www.evalbum.com
The motor controller will probably be mounted pretty close to the motor, so it may be somewhat buried. Did you get any literature for the components in the vehicle?
Another way of looking at is the Tesla Roadster gets ~244 miles EPA from 52kWh, so with 28kWh you would hope to get ~130 mile range *if* your car was as efficient as the Roadster. I doubt it is. Tesla went a lot of rounds of re-engineering to optimize efficiency. I think your car is basically using a lot of "off the shelf" parts not so carefully optimized. Lack of regen is one big example. I would guess you might get something like 100 mile range at a steady 40mph, but more like 70 mile range at 65mph. And that would be with air conditioning off on the flats.
As JRP3 suggested, keeping your tire pressure high could help range. You might want to find out what the highest pressure allowed for those tires. Note, upping your tire pressure could negatively impact panic braking distances, so keep that in mind if you decide to use a different pressure. The vehicle, as converted, probably has a different weight and different weight distribution from the original ICE powered car, so the factory recommended pressures may not really be appropriate anymore anyways.
As JRP3 suggested, keeping your tire pressure high could help range. You might want to find out what the highest pressure allowed for those tires. Note, upping your tire pressure could negatively impact panic braking distances, so keep that in mind if you decide to use a different pressure. The vehicle, as converted, probably has a different weight and different weight distribution from the original ICE powered car, so the factory recommended pressures may not really be appropriate anymore anyways.
I have a Zilla for sale. We are also now offering a controller that is a replacement for the lower end Zilla.
http://www.evcomponents.com/SearchResults.asp?Cat=37
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