Hybrid e30?

[ismellfish2]

Hey there,

I'm hoping to start a project soon and I want you all's opinion as to whether I'm getting in way over my head or not.

There's these plans available online ( http://www.motherearthnews.com/Alter...ectic-Car.aspx ) describing exactly how this guy converted an old Opel to a hybrid/ electric car back in the 70s, with a big electric motor powering the car and a little gas generator supplying the electricity. I want to try and do something similar with an e30.

Things I'd change- he got 75mpg out of his car, but it couldn't cruise faster than 50 for extended periods of time. I'm thinking I'll want a little bigger electric motor and a bigger generator to get around that, and then try and get the efficiency back with a more sophisticated ECU. I'm also thinking I'll keep the clutch assembly, and just attach the output of the motor to the stock flywheel.

I've spent a lot of time working on my e28 and some on my girlfriend's e30. I've got a fair bit of experience with a wrench but not really any with fabrication. I'm planning on taking some welding or metalworking courses over at the technical school to get up to speed.

I don't expect this to be particularly easy or fast, but I'm hoping it's doable. I live with some computer science majors and I hope they can handle a lot of the ECU hardware and software, so I'm looking more just at stuffing a big electric motor under the hood and wiring it up. I think it'd be pretty cool if you could put together this kind of a driveline and still have some good power, and I'm looking for a project to experiment with and learn from. I really want to do something more different than just sinking a bunch of money (which I don't have anyway) into doing the usual upgrades to the e30.

So what do you think? Is this going to be awesome or just a huge frustrating waste of time and money? Thanks!

[BDSax]

sounds expensive. i say try it

[JasonC]

I'm going to say NO.

[mudflaps]

or you could be cool and LS1 swap it.

[Ral]

at least it's different. Give it a try. That's one of the points of modding a car, right?

[apexede30]

Naw. Go biodiesel. case closed.

[Jscotty]

It will be difficult, time consuming, expensive, and it might not even work after the long gruelling hours of labor.

There are a bunch of things that we take for granted with gas powered cars such as vaccuum lines that power the brakes amongst other items, the cooling system that also provides heat inside of the car, and even the power steering and A/C that operates as the result of the ongoing motion of the drive belts. Hybrids don't have all of those "luxuries" so the auto manufacterers have figured out how to make these things work.

I am not suggesting that it is an impossible task, however , I am willing to believe that Toyota spent MILLIONS on developing solutions to the items I mentioned.

[ivo316]

There are several issues you must tacke when building a hybrid,specially because you will be modding your car to be an electric battery car, and a gasoline car.

First is what kind of hybrid you really want to build.

a) A hybrid that will use the electric engine to accelerate up to a certain speed and then run on gasoline.
b) A Hybrid that starts the gasoline engine once in a while to recharge the battery pack.

once you review the pros and cons of each system, then you must choose the kind of batteries you will use:

a) Lead acid (less efficient but cheaper.
b) NiCads (High weight/output ratio, but expensive).
c) Ovonics (if available they must cost a lot).

Then see if you'll go DC or AC.

See if the motor will be brushed or brushless asychronious

Check these guys and what they did (these are full electrics, but they will give you an idea of the power needed to move a car on electric power.

http://www.austinev.org/evalbum/type/BMW

You will find lots of info here:

http://maeaa.org/links.html#High%20School%20and%20University

At Austinev.org there is a great guy called Mike Chancey, he has built several EV's and hybrids, and he answers questions and will direct you to sources of info.

http://www.austinev.org/evalbum/contact

Good luck with your project, I think that it is possible to get 100 MPG out of a Hybrid, let's hope you are the one to doit and in an E30. :D

[TwoJ's]

And electric motors make loads of torque.

[ivo316]

It will be difficult, time consuming, expensive, and it might not even work after the long gruelling hours of labor.

There are a bunch of things that we take for granted with gas powered cars such as vaccuum lines that power the brakes amongst other items, the cooling system that also provides heat inside of the car, and even the power steering and A/C that operates as the result of the ongoing motion of the drive belts. Hybrids don't have all of those "luxuries" so the auto manufacterers have figured out how to make these things work.

Sorry to disagree, but there are electric servo pumps, power steerign pumps, electric ceramic heaters, electric air conditionerc drives, and are all "off the counter" items.

[ivo316]

And electric motors make loads of torque.

Right, in fact the torque curve is flat, you get the same torque throughout the whole rpm range. ! :)

[browntown]

here's my thought, making a electric hybrid is going to cost a fortune. An easier route would be to swap in a diesel out of an ancient 5-series (I've seen one), then convert to run on vegetable oil.

Mercedes mechanical injected diesel's will do it out of the box. Keep your regular e30 to pollute with on the weekend and daily an early 80's merc 300D for no money and smell up your neighborhood with the smell of french fries. I know two people motoring around on french fry oil in the old mercs, they run forever.

GREASEL FTW.

[Jscotty]

Sorry to disagree, but there are electric servo pumps, power steerign pumps, electric ceramic heaters, electric air conditionerc drives, and are all "off the counter" items.

You shouldn't be sorry about disagreeing.

Secondly you are right- You can walk into Grainger or some other tool/equipment supply and purchase just about everything you need. The point I was making is that you still have to be able to engineer that stuff so that you do not end up making a car that can go a distance of only 8 miles.

Speed and distance has always been the hardest thing to overcome when dealing with electric cars and hybrids.

[Maluco]

natural gas....

[ismellfish2]

There are several issues you must tacke when building a hybrid,specially because you will be modding your car to be an electric battery car, and a gasoline car.

First is what kind of hybrid you really want to build.

a) A hybrid that will use the electric engine to accelerate up to a certain speed and then run on gasoline.
b) A Hybrid that starts the gasoline engine once in a while to recharge the battery pack.

once you review the pros and cons of each system, then you must choose the kind of batteries you will use:

a) Lead acid (less efficient but cheaper.
b) NiCads (High weight/output ratio, but expensive).
c) Ovonics (if available they must cost a lot).

Then see if you'll go DC or AC.

See if the motor will be brushed or brushless asychronious

Check these guys and what they did (these are full electrics, but they will give you an idea of the power needed to move a car on electric power.

http://www.austinev.org/evalbum/type/BMW

You will find lots of info here:

http://maeaa.org/links.html#High%20School%20and%20University

At Austinev.org there is a great guy called Mike Chancey, he has built several EV's and hybrids, and he answers questions and will direct you to sources of info.

http://www.austinev.org/evalbum/contact

Good luck with your project, I think that it is possible to get 100 MPG out of a Hybrid, let's hope you are the one to doit and in an E30. :D

Thanks for all the feedback! These links especially are great, I wasn't aware anybody had used old BMWs as a platform for EVs.

I hope I'm not looking at a whole lot of money here... the biggest component I'll need is the electric motor, which I'd planned on getting military surplus or something like that for not so much. The guy who wrote the plans I'm going off of used a motor designed as a jet engine starter (!). The generator will just be some sort of little lawnmower engine and an alternator. I mean, I'm sure it'll run me a couple grand at least, but that's not all that much compared with more straight up modding. I'm planning on financing some of it by parting my old e28, and by selling off whatever's in the engine bay when I buy the car (plus the exhaust and any other stuff I won't need).

As for the distance/ power issues, I think those are helped a lot by the fact that my electric generator will be on board. The prototype the plans come from didn't really have any range issues, just speed- which I hope to address with a slightly bigger generator.

I don't know that much about the physics of electricity, to design my own system; I'd hoped to get around that by going off these plans and by crash course-ing. But in response to ivo316: b), gas powers the generator only, DC (I would think), and brushed/brushless- no fucking idea. I'll have to get up with Mike about that, thanks for the reference!

I know those biodiesels are pretty sweet- there's a guy out near me named Al Taylor, who you all might know since he does a good business in parts, who's done well with his biodiesel Bavaria racecar. I'd be interested in using a biodiesel engine for my generator. However, I'm into the whole flat torque curve thing, and I can't afford a Tesla Roadster!