I'd rather have wide 18" or 19" diameter. There are more options for track tires, including Pirelli GT or Tudor/rolex/weathertech take offs for 18". Ive got 19" that cuts acceleration compared to 18". Going to 20" will give you more top end, arithmetically but it'll cut acceleration by the a similar factor. If you are a 1 mile fan, makes sense, but if you are track or street, 18"/19" will give better acceleration. Kinda like adding 5% more horse