[LAP1DOUG]

The main handling result of spacers is to decrease lateral load transfer in a turn. Lateral load transfer is primarily a function of the mass, center of gravity height, and track width, with track width as the divisor in the equation.

In my experience, increasing the track width by a total of 20-30 mm can be worth about 0.2 seconds on a 60 second autocross course, and I would expect about this same results on a road course, but you will never feel it unless racing at the absolute limit.