Looking to get better performance out of a 305 with a four barrel Quadrajet and single exhaust. I live in Portland Oregon and we have a pretty tough emissions testing program that limits my options. I can do some exhaust upgrades but have to stay with a single catalytic converter. I can get a new converter that has two 3" pipes in and two 3" pipes out for $190 (ouch!), then go to a dual 3" exhaust the rest of the way out. Total cost around $500. Will it be worth it? Other than exhaust where else would I be able to find more fun? Would like suggestions on what would be the best bang for the buck. I'm not looking to get to radical.