Edit: my apologies for switching back and forth between lbs and kg. I'm in the US and tend to think in terms of lbs.
cheapcookie wrote: ↑
Jun 24, 2018 5:58 pm
Thank you, mostly functional is not what I am going for, I will try to get rid of as much stuff as possible, will have to see about power steering.
The car would probably be left with one seat, windows replaced with polycarb...
When I said "mostly functional", I meant "mostly recognizable as a car that could be taken on the street. My point with this upcoming wall of text is that your weight savings estimates are WAY off.
I really do not know how you intend to get a 740(?) wagon rolling shell down to 600kgs (1400lbs) before you stuff it full of batteries, let alone with motors/batteries. I can see somebody getting a 740 street car down into the low-3000lb range, which means if you pull all the doors and leave an interior with a single racing bucket and no dash, you can probably get into the high 2000lb range, or low-mid 2000lb range once you pull the engine out.
Budget street/autocross build of a 740 wagon, with 250-300lbs of weight reduction:
https://grassrootsmotorsports.com/forum ... 804/page1/
Here's some info about weight reduction measures that were done to get 200kg's off a 740 turbo race car.
You can absolutely get a bunch of weight off the car, but you're not getting away from the fact that the body of your chosen donor vehicle has a LOT of very thick steel that you are not going to want to cut out. If you started with something front wheel drive, you could get it a lot lighter (since you don't have to worry about the rear axle/diff and driveshaft).
A Volvo 240 Group A race car weighed around 1050kgs (~2300lbs) in race form, with steel body panels that had been acid dipped to make them thinner (along with stock-shaped but thinner hood and trunklid panels) and an aluminum roll cage. Pull out all the cage and racing-specific safety equipment, and you can probably get it under 1000kgs (2100-2200lbs, approximately the weight of a stock early 90's honda civic). This is what a factory-backed racing team could was able to make out of a 242 turbo, which weighs around 3000lbs, not a 3700-3800lb 740 wagon.
Remove the engine and whatever accessories they kept on the race car (call it 350lbs), the doors (the race car already had lighter doors, so 30-35lbs each) and you're around 1700lbs (7-800kg) before you start loading it up with batteries/motors/controller.
Let's say we started with a different donor.
If you started with a small-to-medium sized japanese front wheel drive sedan, you can get things quite a bit lighter. Because I'm a honda nerd and can find that info more quickly, a 1994/1995 Honda Accord LX sedan weighs 2800lbs with a full (cloth) interior, and power windows/locks (the EX weighs more because sunroof and power seats). 4th gen accords (90-93) are boxier and not quite as aerodynamic, but weigh about the same. Personally, I'd really like to convert an old 87-91 prelude with 4 wheel steering at some point in the future.
Here's some of the component weight info for a 4th gen accord:
Starting with a 2800lb car, you can relatively easily get it down around 2500lbs before you've even made the thing uncomfortable (still have stock front seats, doors, airbags, power windows, full interior ahead of the B-pillar, stereo, etc), let alone questionably-street-legal. There's another 50-ish lbs there if you replace the stock front seats with lightweight buckets. Replace the rear glass with fixed lexan and remove the window regulator and tracks/supports for another 25-30?lbs or so. Get lighter wheels and you can absolutely get one of these into the 2300-2400lbs (under 1100kg) range without ruining it. At which point it'll be a fun little car to bomb around town with (at stock weight they handle pretty nicey, a 400lb diet makes it accelerate/brake/handle much better).
I've seen people get them down to 2100 and change for racing.
As far as stuff you don't need for an EV, the engine with all manifolds will be another 250-300lbs, fuel tank is like 20lbs (plus figure another 60lbs of fuel from the above weights), exhaust is probably 30-40lbs, and you're probably going to be between 1800-2000lbs. Pull off another 200lbs for race mods that would make it unsafe for street use. And I guess another 30-40lbs each if you really want to drive around with no doors, which will destroy aero and might not be legal where you live. Now we're starting to get closer to your original target weight. The transaxle weighs another 80lbs, but I'd leave that in place because it's going to be very useful.
Then it's just a question of how many batteries you want to stuff into this thing.