i have the original manifolds and exhaust all the to back even the y pipe . but i cant use the manifolds on my 350 so can i get manifolds or headers that will bolt up to the ypipe, or do i neeed to have it all replaced

 

Others here know a lot more about this than I do, and hopefully they will chime in with some good information for you.

What I do know is that the exhaust system designed for a 305 will significantly restrict the flow of exhaust on your 350, increasing back pressure, and costing you some serious HP loss. If it were my car I would install a good set of headers and than complete the system with one of the better aftermarket dual exhaust set ups. Some companies make a complete package.

Are you required to have a cat in the system to pass inspection in your state? Our state requires the cat to be in place and look functional, however in vehicles older then 15 years old they do not test it. There is a visual inspection to make sure all of the parts are present.

 

 

3rd gen exhaust systems suck. get a set of shorty headers and a matching exhaust, it's worth it. if you insist on using manifolds, grab a set of LT1 manifolds. They flow way better than just about anything else available manifold wise for a gen 1 motor.

there's no reason the 305 exhaust won't work on the 350, in fact, I wouldn't doubt that the 305 and 350 manifolds are the exact same casting. but as I said earlier, they suck either way.