You mentioned that the EPA was set the same, does this mean its 120% (for example) left and right or is it set for lock to lock on each side (mine arent the same left to right)? I would tend to think something is binding if you're noticing different handling characteristics. If it works properly on the majority of the track and is only abnormal in one or two areas, I'd suspect the track. I've had similar issues in the past and found the springs wasnt sitting on the cup properly. Last week, one of the Avid springs I was using was sitting in the cup funky, the end of the spring was pushed to the inside of the normal radius and the next coil pushed past it and was sitting on the cup. The caused the car to pull to the right while I was going through the bumps and was turning better one direction than the other. Took me a while to figure out what the hell was causing the problem. Something else to look at is how tight the shocks are on the upper mounts, they should be able to swing freely on the upper pivot ball.