I had to take my 16'' rims off the back of the car today, 'cause I had stock 14'' in the front and I was tired of the car looking like a whitetrashmobile. And before you ask, I did not put the 16'' rims that I have for the front, on the front, 'cause the tires are bald and SEVERLY out of balance, and I don't have the money to have them balanced or to buy new tires. Anyway, I was on my way home and put it at 3/4 throttle from a dead stop. When it shifted from first to second, I got wheelspin. Is this normal? As far as i know, everything is stock, except for the headers. Also, it is an automatic. The tranny also jerks a bit when shifting from park to drive, and it shouldn't be the mount, 'cause that was just replaced.

Also, when I was taking off the spacers, both wheels rotated towards the front. So, would I have a one-wheel rear-end, limited slip, or true posi? Or is the only way to tell is to hammer it from a dead stop with someone watching to see if both wheels spin?

 

Most likely the height of your tire is somewhat shorter with the 14" wheels, thus raising your gear ratio numerically. This probably accounted for your increased acceleration.