Do our cars have a form of Limited Slip?
 

I got into a friendly argument today with a coworker. He's insistent that every car has a partial Limited Slip Differential. He claims that if Im in 1st and mash out, I'll lay down 2 sets of tread, that both wheels will spin equally? (As long as Im going straight) I have tried this and only see one each time I try. Is this true and I could have something wrong or is he wrong?

no accent comes from the factory with a limited slip

If they both lose grip equally then you can spin both with an open diff. If either starts to slip first it will be the only one spinning. Its not a partial limited slip, just how an open diff works.

Don't forget that there are a million other variables: differing axle windup, the camber on the road, a difference in wheel alignment etc... you might get two wheels spinning up on a variety of surfaces but there's enough noise and friction in the whole equation that you'd never get a car to always exactly follow what the textbook says.

I hope you made a bet, because you won.