Check out this page for background. http://farnorthracing.com/autocross_secrets7.html
If the rear is coming out, its oversteer not understeer. I run my car with about zero rear toe. I think +1 rear could be adding to the oversteer...
Parking Lot Hero
2008 WRX daily driver
2003 ZX3 23D Autox Car 42 FSP
"Hella Functional - Raced, Not Hard Parked"