Mopar,
the Silicone couplers are joiners to allow flexing of the exhaust when A rigid 1-piece cannot be used; and/or to allow minor changes to the exhaust's overall length. It is not intended for bending.
The exhaust system for your engine is designed to carry a pressure wave away from and back to the exhaust port. Changes to the inside-diameter (by bending) or any type of deformation will have a direct and dramatic effect on the exhaust's efficiency. You can come up with your own exhaust to fit your needs but you need to have some performance criteria laid out before you piece things together. You can really quickly spend a lot of money just to have cobbled together muffler.
Tell me what you got (engine & Pipe) & what you are trying to do and maybe I can give you a few generalities that may help you out