What alignment angle is likely altered by moving the top of a MacPherson strut tower inward?

The alignment angle that is likely altered by moving the top of a MacPherson strut tower inward is camber. Camber refers to the vertical tilt of the wheels as viewed from the front of the vehicle. When you move the top of the strut tower inward, the upper portion of the wheel assembly is angled more towards the center of the vehicle, which results in negative camber.

This change affects how much contact the tires have with the road, impacting vehicle handling, tire wear, and stability during cornering. Proper camber alignment is essential for optimal tire performance and ensuring that the tire's tread makes even contact with the road surface.

Other alignment angles, such as toe, caster, and SAI, are less directly affected by this adjustment in the strut tower position. Toe refers to the angle of the wheels in relation to the vehicle's centerline, caster is the angle of the steering pivot point, and SAI (Steer Angle Inclination) impacts the steering geometry but does not change because of adjustments to the strut tower's position. Thus, the movement of the strut tower inward primarily influences the camber angle.