I usually get 2.1-2.2 on my 60' with some retreads. You have to get the right amount of clutch to match the right amount of gas. It is a chess match to figure it out but once you get it you have to remember exactly what you did.
What is the 60' and why is it so important? Most races are won during the first 60' (unless it is an obvisious mismatch). You see timeslips all the time with high ETs and high MPH. That means they are spinning at the start and therefore losing valuable time. .2 off your 60' can = as much as .4-.5 at the end.
hope that helps you understand it a little more.