Quote Originally Posted by Chip42 View Post

explain the A comp on the rear thing... more grip on the rear = good why? or is there a weight issue or something else I'm missing?
Nah, it's not really a "more grip" thing more a matter of how quickly the rear end comes up to "normal" grip levels. On R's, a "fast" CRX is a handful for the first couple laps as the fronts gain heat/grip more quickly than the rears. Put R's up front and A's in back and they should come up to temp/grip more or less equally which lets you gain time in the first couple laps. Total grip potential at operating temp is (effectively) the same for the rest of the race and the rears never get so overloaded that they can go off or get greasy.

Disclaimer: this ^^^ is second hand info from folks who've gone down the road of staggered compounds. As much as I liked the theory of it, I preferred the ability to easily rotate tires front/back and even out wear and heat cycles.