I'm surprised with all the 255/3.23 theorists. I got a similiar mild built 360 with 3.55 and 305's and a tighter converter can't keep the rear tires stuck. Something in the OP's tune is off, I don't see a drive train issue, except the 255's are too narrow.
Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.
