Installing 1 inch wheel spacers is a very SAFE and popular fitment for stance cars.
Quality spacers are made of aircraft-grade billet Aluminum that is strong enough to avoid being the weak link in your setup.
We have seen them work successfully on countless track events.
Racing with 1 inch wheel spacers has no problem.
Actually, some automakers equip factory cars with wheel spacers as many racing teams have done this regularly over the years.