I have the hotbodies undertail exhaust and I gain like 6hp. I am taking the Akrapovic full system and replacing that damn wack azz hotbodies sh$t. Lee told me I would gain 6-9 hp with a akra or tiforce full system. I have 169rwhp now with the hotbodies? What would be around what I will have when I swap out the hotbodies for the akra or the tiforce?