There's been quite a few instances where, given the proper motivation, regular folks have been capable of some pretty extraordinary feats of strength, including lifting up cars.I have a few questions..
Strength 6 is the max a normal human should have but in the strength lifting chart you can lift a car? Is this right or an error?
I have a character with Leaping 3. How far is that? The Leaping power entry only takes about level 7 and beyond.
I'd think a strength of 6 should let someone like Capt. America (the pinnacle of human potential) could feasibly lift a car with the proper amount of effort.
But in this case, and your question about leaping, just do what feels right for your game. If you don't want non-supers to lift cars, change the scale slightly. With Leaping 3, just make a judgment call (say 50 yards or so), but keep it consistent within the confines of your game.