A converted Ford Tempo for sale. Assuming the seller's claim of 40 miles range is accurate, and that range is say, at 60 mph, then aeromods, LRR tires, synthetic oil, and other simple mods could increase that to 60 miles on that same battery pack at that speed.
Fitting something like this with 20 Universal Battery UB121100s(80 AH at 1 hr rate, 2V nominal, ~720 CCA, .004 ohm impedance), a Zilla 1k, and 9" motor would be a very quick car with perhaps 80-100 miles range if it has decent efficiency mods.
The current pack in there is 120V nom, 135 AH at 20 hr(~90 AH at 1 hr), so that's a total of 10.8 kWh on board. At 40 miles range, that's .27 kWh/mile, which sounds very reasonable for a midsize car with normal aerodynamics. I bet aeromods, LRR tires, synthetic oil, adjusted alignment could get all of that down to about .18-.2 kWh/mile, which would also draw less from the battery thereby extending AH available(Peukert's effect), having a double whammy efect on range.
Now, imagine fiting in a monster pack of UB121100s, 240V, 80 AH at 1 hr rate. Say, .2 kWh/mile. Works out to 96 miles range. Not too shabby. 20 UB121100s though weighs in at 1,460 lbs. You'd need some hella springs to handle that weight, as you'd definately be over GVWR.
Zilla 1k, 9" motor in say, a 3,200 lb conversion would yield 0-60 mph ~8 seconds if the battery can maximize the potential of the motor to produce power(At 170V and 1,000 amps, ADC/WarP 9" motors are about 60% efficient, you'd get about 140 HP max from the motor and need about 230 HP from the batteries to do that). Top speed would definately be beyond anything legal.
If I had the cash, I'd love to convert a Tempo. They just lend themselves so well to modification. A freind of mine has one and it appears to be an almost optimal platform for conversion, at least if you need to seat 4 people(If you're willing to settle for 2, then the GT6 would be much more efficient/faster). This one is already converted, and it's a relatively simple matter to swap in new parts. That, and Tempos are very fun to hotbox.