Wehrli Custom Fabrication is an Industry Leader in Duramax Turbo Kit's and Custom Parts. On the Forefront of Turbo Kit Development we strive in producing the Best Product on the Market. You can rest assured that with the Purchase of our kit you will receive the Best Quality Product, Fitment, Customer Service, and Performance for your Truck. Whether it be to outfitting your truck with our popular s400 over stock Twin Kit, or if you’re looking for Four Digit Horse power numbers, we can handle it.