Proper grounding may smooth out the powerband slightly if the vehicle was poorly grounded to begin with. However, you probably wouldn't even notice much of a difference, if any, between the use of an aftermarket grounding block and just using the stock grounding locations and straps that are in good condition. If you come across an aftermarket grounding kit for relatively cheap and have some money to throw around, go for it, but you're probably better off looking for power elsewhere.