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Electric 240z Project Pics


jmead

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I know you said your '76 has a lot of sentimental value for you, and I can fully appreciate that, but do you think it will be for sale when you're finished converting it?

 

Jeff

 

Hard to say, I'm not looking forward to selling it, but there is a pretty good chance it will have to go to make room for the next project. Ideally I'd know before hand so I could design things around a goal, be it performance or economy or style. Are you in the market for a 280zev?

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  • 3 months later...

I know the last post was back in October '08, but how the things are going? Have you finished your 76? I have a 76 as well and am wondering if I install a generator in the smog equipped car even with the eletric motor (I live in CA), am I going to be penalized for running diesel down the freeway? :-) Can one run a farmer's diesel in a generator (cheaper)?

 

How much more difficult is it to install the direct drive system bypassing the transmission?

 

Thanks!

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  • 4 months later...
I know the last post was back in October '08, but how the things are going? Have you finished your 76? I have a 76 as well and am wondering if I install a generator in the smog equipped car even with the eletric motor (I live in CA), am I going to be penalized for running diesel down the freeway? :-) Can one run a farmer's diesel in a generator (cheaper)?

 

How much more difficult is it to install the direct drive system bypassing the transmission?

 

Thanks!

 

The 76 has been prepped (engine removed), but nothing else has been done. I've been swamped with no less than 4 other EV projects all happening simultaneously. Plus, I would really like to convert the 280 without running anything to the back; keep 100% of the batteries and wiring under the hood this time. This will make things way, way easier, but it requires I use lithium batteries. To do it with lead would only be possible with a small, light pack, which would compromise range significantly. I don't want to compromise anything.

 

The diesel was removed when the car was sold, I never got a chance to run it while on the road. The start/stop and speed control was going to be an issue without computerized control, which is tricky on a primitive engine.

 

As far as "farmer's diesel"....I have no idea. My understanding is that if you're caught running off-road diesel in a road vehicle the fines are incredible. But when that diesel is running a generator that runs a vehicle....thats a grey area. If I had to guess I'd say its perfectly legal to run that generator in your driveway, but the second you start moving you're in violation unless you pay the road tax.

 

Here is what I would do; make it removable. If you run into smog issues you just go home, pull it out, and you have a straight EV. Could swap in a cat'ed engine, hydrogen fuel cell, second pack, whatever makes them/you happy without too much trouble.

 

Direct drive....way easier. Haven't tried it personally, but so much of the fabrication was the motor-trans coupling it'd go much more quickly if it could be avoided. Plus, if I had to list what was most likely to fail under abuse, it would be that coupler. To get rid of it makes the whole vehicle so much more elegant in my mind. Since you stick the motor where the transmission was, you free up the whole engine bay for batteries (better weight distribution possible).

 

Direct drive requires alot more motor (8" is plenty with a transmission, 9" minimum for direct and I'd go with a 11" personally) and more controller (1000A was fun with a trans, I'd want more if I was going direct). Counter-intuitive, but battery requirements are unchanged.

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  • 4 weeks later...
Hey man are you selling this?

 

I have been browsing the forums looking for the right car for me. Either way, sick car.

 

Already been sold.

 

Now I'm working on a 52 Ford F-1 and a 76 280z that will put the 240z to shame. (800 ft-lbs vs 250, 300lbs of LiFePO4 vs 700lbs of lead, etc). Updates will follow when I've got more to show.

 

Ultimately I want to start building cars for people, so if you're serious PM me and we'll talk. :)

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  • 2 months later...

hi all,

 

I am pretty new on this website but I have been following the discussion about EV's for a pretty long time now. The ZX conversion is really a state of the art project! I am wondering if it would a idea to remove more from the old design (internal combustion engine related parts) and put the drive directly on the wheels? Every power transmission part normally is a loss of energy (I mean every coupler/coupling) and removing parts/weight is what one is trying to achieve I think.

 

How do you guys think about a DC motor on both of the powered wheels or even on all four of them?

 

Just sharing my thoughts here, but I think this is what this forum is all about :)

 

Kind regards from the Netherlands, Europe,

 

Marcel

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One of the things that makes that difficult though is avoiding unsprung mass. You really don't want to add a 20 pound motor into the mix, let alone the much heavier motors required for most applications. In theory you could run a single motor where the differential is with outputs on both sides, but without any clutch system involved for each side you'd end up with the same setup as a welded diff, which doesn't like to turn kindly.

 

For sake of simplicity, the farthest you could remove the stock drivetrain would be to cut out and reshape the floor right in front of the diff and mount the motor directly to the diff, allowing removal of the driveshaft and transmission. The only concern here is that you need to make sure you're not going to overheat the motor at lower speeds, and not go beyond it's RPM limits at higher speeds. A larger motor is less likely to overheat, but of course it's larger and harder to fit into the space requirements without impeding upon the passengers.

 

Though to be honest I'm not the most educated on electric vehicles, so maybe someone else will chime in with their points on the matter.

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i wonder if there is some way to generate electricity using the wheel hubs (car goes down hill, wheel hubs spin around a stationary magnet)

 

i've thought about that too. maybe the car could even charge itself while propelling itself. i'm not really smart enough to figure it all out, nor do i want to try, but i've always wondered as well.

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Regenerative braking is a form of kinetic energy recovery, so let's make sure not to get our terms crossed or anything. They're very much related and/or the same in many ways, not separate ways to do the same thing.

 

jmead in his project process talks about how the motor/controller combo he chose to go with wouldn't be able to perform regenerative braking, mostly due to the cost of such systems.

 

Many of the hybrids and most of the expensive electric cars have regenerative braking which does help considerably. This is purely my opinion, but I believe this is the #1 reason hybrid's actually get better mpg. Hybrid's get what seems to me the same MPG on strictly highway use than the same car would get with the same gasoline engine it already has, while in city it's significantly better. In city the hybrid can get off the line in electric mode which is where gasoline engines suck back the fuel, and then once you're going the gasoline engine can take over. During braking much of the energy it took to get off the line in the first place is put back into the system via regenerative braking.

 

This is a very crucial system for hybrids because you can't expect the gasoline engine to create a charge and get more than 100% of that energy back, meaning that if it's taking 10hp to keep the car going, and then you tack on another 10hp for battery regeneration giving a total load of 20hp, you're not going to get more than 10hp back for an equal length of time, that would be called perpetual energy which is something we have yet to invent.

 

What I'm getting at is that any way you look at it, is that what you're talking about KROz is already being done, and done very well I might ad. You're only ever going to be able to make a car go so much farther with techniques like this because there is always going to be waste energy in a car somewhere or another. The main thing we could do to improve the existing system would be to half rolling resistance without loosing grip on the road. This would allow less energy to keep the car going and thus more of the energy put into getting the car started would keep it going at a desired speed.

 

This is also why MPG freaks run their tires at max PSI, to the point of danger in some cases. The higher PSI lowers rolling resistance, but also reduces considerable grip in most cases. To be fair though, running higher psi levels than most people do can be much safer in rainy conditions because the tire cuts through the water better making it less likely to hydroplane.

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[quote name=

For sake of simplicity' date=' the farthest you could remove the stock drivetrain would be to cut out and reshape the floor right in front of the diff and mount the motor directly to the diff, allowing removal of the driveshaft and transmission. The only concern here is that you need to make sure you're not going to overheat the motor at lower speeds, and not go beyond it's RPM limits at higher speeds. A larger motor is less likely to overheat, but of course it's larger and harder to fit into the space requirements without impeding upon the passengers.

 

[/quote]

 

Seems to me that spinning the diff around and putting the motor where the gas tank was would be the better route. This would be both easier to cool and help offset the weight of the batteries in front.

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Seems to me that spinning the diff around and putting the motor where the gas tank was would be the better route. This would be both easier to cool and help offset the weight of the batteries in front.

 

Why didn't I think of that? Not a bad idea actually in my opinion.

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The motor could be mounted above the diff parralel to it and bolted to the existing holes/studs in the diff itself. The drive could be a timing type belt similar to the Harley. This way the whole drive would move together and be isolated from the car. Number of teeth in the pulleys could be varied to determine the final drive ratio.

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awd transmission? why even bother for a transmission at all? The e-motor has full torque from rpm=0 until full rpm. That is why you could put an e-motor on every wheel. Despite of the post I read about two e-motors on let's say your frontwheels would act like a welded axel.. That aint the case because the e-motor will always have it's tolerance in the rpm due the curve that you make. And if you even worry about that, why not put a controller in that keeps tracks of the angle your frontwheel make (to turn) and let it adjust the rpm of the inner-curve wheels with regard to the outher ones.

 

Electronics have no limits, it's just how we use them :-)

 

Marcel

hobbyguy (in electronics & metalworking)

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awd transmission? why even bother for a transmission at all? The e-motor has full torque from rpm=0 until full rpm. That is why you could put an e-motor on every wheel. Despite of the post I read about two e-motors on let's say your frontwheels would act like a welded axel.. That aint the case because the e-motor will always have it's tolerance in the rpm due the curve that you make. And if you even worry about that, why not put a controller in that keeps tracks of the angle your frontwheel make (to turn) and let it adjust the rpm of the inner-curve wheels with regard to the outher ones.

 

Electronics have no limits, it's just how we use them :-)

 

Marcel

hobbyguy (in electronics & metalworking)

 

Which is why I stated that would only be an issue if you were using a SINGLE motor without a diff, a motor that had two opposing outputs on a singular motor.

 

Why do this? Because mounting motors at each wheel WILL add an insane amount of unsprung mass that SHOULD be avoided at all costs for anyone making a performance oriented (even mildly) project. You "could" use 4 smaller motors mounted to the chassis with axles running to each wheel, but at that point you have to as why. You have a perfectly good diff sitting in a RWD car, why not use it? Sure you CAN use an electric engine with direct drive thanks to it's instant torque output, but you must also remember that the heat and load generated from doing that is great and should be considered. Even an electric motor likes a torque multiplier.

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