I want to redo the exhaust on my 85 poncho. I'm debating on a 3 inch single or true duals. Now many of you know that the boxys didn't come with a dual hump cross member. My thing is duals at my local shop were gonna cost me $600 with no cats $800 with. I've heard that a full 3" will flow as well as duals. Also i'm hoping that it would be cheaper. I do play on dropping a stroker in the car eventually. Currently it has a 350 with stock manifolds. Also I live in florida and there is no emissions. Should I run a cat or no cat. If i run no cat will i lose back pressure?