I used 1.5 inch leafs and then I used different thickness lowering blocks (1"..1-1/4, 1-1/5) to tune the car at autocross events..the lower the car the more push/traction, the higher the car the better it rotates on tight corners.....the base setting was the 1.5 leaf with the 1inch block, and I changed block after a few runs if needed
