In forza if you place a wheel with a negative (or positive) offset, it will be placed on the car according to where the sidewall of the stock tire sits. This creates the effect that the axel, suspension and brakes are being moved inboard or outboard on some cars.
Here are some examples.
Stock 2002 Camaro wheels…
Compomotive wheels with a positive offset…
Notice how the tire is in the same position as the tire on the stock wheel. and look at where the brake caliper is on the Compomotive wheel. Did they install some extra axel length in between the knuckle and the wheel hub or something?
American Racing wheels with a “deep dish” negative offset…
The AR wheel is shown to illustrate that the opposite also happens. What isn’t shown is the brakes moved inboard. This makes it seem like the axel and suspension have been moved inboard to accommodate the wheel.
The way wheels sit on cars needs to be addressed and reflect what really happens when a wheel is mounted to a vehicle.