Subaru 2002 IMPREZA Service Manual page 1905

Thrust angle: r = ( α α α α − − − − β β β β )/2
α: Right rear wheel toe-in angle
β: Left rear wheel toe-in angle
NOTE:
Here, use only positive toe-in values from each
wheel to substitute for α and β in the equation.
(1) Front
(2) Body center line
WHEEL ALIGNMENT
B4M0194B
FS-15
FRONT SUSPENSION