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Originally Posted by puddleglum
Are you wanting to pull 400lbft torque from your electric motors in addition to your gas engine?
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At first, just to get things going, I would like to use the small, cheap motors to see if I can get them to work, as well as see if there is a noticeable performance gain. After that, assuming I am satisfied with the results, the real money spending starts, including buying more powerful electric motors and getting performance modifications for the gas engine as well.
Quote:
Originally Posted by puddleglum
Did Chevy make your car with a 4WD option? Are you thinking of having the motors direct drive to the wheels?
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No, and Yes.
My car is based off of the GM W Body platform, which has had no AWD or RWD vehicles. However, I have read about people doing RWD conversions on W body vehicles using rear axles from certain GM suvs, such as the Pontiac Aztec, which I may be able to find a rear axle of for very cheap.
Quote:
Originally Posted by puddleglum
Do you have room to mount both motors end to end and still run cv driveshafts to the wheels?
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If you mean perpendicular to the wheels, then maybe.... If you mean to mount them longways along the center of the undercarriage, then I seriously doubt it.
I managed to look at the underside of my car once while it was being serviced, and took some pictures as well. Do you think I can fit 2 small electric motors in this space? What are these things, and can they be removed? Do you think it will be difficult to connect the motors to the frame of the car? I am definitely not opposed to a new exhaust system to make it work. Also not opposed to losing my spare tire space if that will make the room that is necessary.
Quote:
Originally Posted by puddleglum
Series motors don't self limit their max rpm so if you ever spun a wheel on a slippery spot it could overspeed the motor and do damage. A single motor through a diff. would be easier and cheaper. The brushes will be wearing even when the motor isn't being used and if you do use a diff, you need to be sure you gear it so you don't over speed your motor at top speed. AC motors are much easier to control and will do regen, but will cost even more and finding low speed/high torque motors could still be an issue. If you lower your performance goals, you might be able to fit hub motors to the rear wheels but they likely won't have the torque you want.
When you are talking battery pack you need to pick batteries that can deliver the high currents you want as well as the range. Once again more power means more money. High quality lithium will be a must.
I think anything can be done with enough time and money, the question is how bad do you want this?
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Now all of that is good info for me. Definitely haven't heard about most of those issues. Basically, here is how bad I want this:
If I have to completely mangle the undercarriage of my vehicle in order to try and fit electric motors along the center, to then go into a diff off of a random SUV, then it may not be worth it to me, just because that is only half of the work, and will be very expensive.
However, if there is any chance of getting this to work by mounting the motors directly to the wheels along the space that a rear axle would be, then yes, I definitely do want to do this. Remember that I can use the front drivetrain to do anything other than go fast in a straight line. The economy stuff is just something that I would like to do if possible. If it would make this whole project THAT much more difficult, then I would totally just leave the motor off until I got to the strip.
That being said, I don't actually know what is under that undercarriage cover. If I find out that there is room for 2 electric motors to be coupled to each other and run through a differential, and that moving the gas tank isn't as hard as I think, then I would totally do it.
The other option is using one single powerful electric motor that is double-sided to drive both wheels. This basically means I will have a locked differential, which may not be ideal, but then again, this car is going to be just for straight lines. I have already had a close enough call involving a slight curve on a long, high limit road, where torque proved to be a scary thing. I do not ever want this car to be over 3k rpm on an even remotely curved road. Basically, if I have to simply not use the electric part of the car if it is wet, or if I am on a gravelly road, then I wont.
That motor has about a 12 inch diameter, which means im pretty certain it can fit in that cavity. However, the reason I think 2 separate motors would be better, is because they will actually put out more power, while also having a smaller diameter. If the gas tank is in the way for the 12" motor, then perhaps it won't be in the way for two 9" motors. Then the question would be whether to couple the 2 motors into one, like in this video, or have them each drive a wheel by themselves.
They have a 13" motor that puts out much more power, but is also much more expensive.
Thanks a lot for your comments. I hope you can make more sense of what I want to do now, and, hopefully, tell me about how totally possible it is.
