Let us know how it runs with the new pulley and tune. I just bought one a few months ago, but it just sits in the garage. I only have 650 miles on it. I already have an SCT II that i had from another truck, i just need to get it reprogramed. Do ya'll think just putting a custom tune will help any with the truck? Also, does putting a custom tune on the truck leave any kind of signature when i put it back to stock?