Q: “I compete in a very grassroots series, predominantly filled with 900kg 1.5L Korean hatchbacks running cheap but soft street tires. One thing I’ve noticed some of my competitors doing on entry to a second gear hairpin is they turn in really aggressively. So much so that the inside rear tire lifts momentarily. Do you think there is an advantage to doing this? My thought is that it unnecessarily loads the front tires on corner entry, but maybe it also generates a touch more heat for more bite? They don’t seem to be getting a better corner exit than I do, but my eyeballs aren’t the most accurate data gathering system.”
A: I’m guessing that these are front-wheel-drive (FWD) cars? For a FWD to lift the inside rear tire is a very common thing. Hey, you might even learn that you’re doing the same thing, as the load transfer in these types of cars causes this often. It does help rotate the car – so it’s not a bad thing. Many FWD cars tend to understeer into a corner, and the best way of managing that is to trail the brakes into the corner, keeping the front tires loaded and rear unloaded. That unloads the inside rear so much that it lifts off the track surface. And even if it doesn’t lift completely off the track, it’s so lightly loaded that it’s not providing any grip to the rear of the car anyway. That’s what helps the car “rotate” (change direction; a deliberate use of a little oversteer). Yes, it might be caused by an aggressive turn-in, or it might just be what these cars do due to the tire and suspension setup.
So, is there an advantage to this? Most likely. By getting the car to rotate, the car will now be pointing in a direction that allows you to get on the throttle earlier – and that’s a good thing. I think it has less to do with tire heat, though, and mostly due to the ability to rotate the car.