So I've recently got back into playing GTA5 and a thing that i'm slowly becoming interested in was racing.. I have heard a lot of different things so i wanted to ask some of you guys.

1) Does armor slow your car down at all?
2) Does different sets of tires matter? (I've heard that off-road tires are best for races because they can handle curbs/bumps better.

And if you have any tips/tricks for cars or anything of that nature for racing let me know.

Thank you in advance for your answers.