I have an 84 z with a basic 350 motor and I put a full flowmaster exhaust but never got the cat. What are the benefits of having or not having It? Thanks all.

 

it's up to your state regulations and not up to what you wish to do.

Soooooooooooo, if your state has emission testing then you probably need the cat.

 

well im not really concerned about state inspection.... my car is old enough i dont need it. i am more looking at will it make the exhaust smell of gas go down or not? i have gotten the car tuned to run perfect but it still smells very strong. . . unless that is just how carbs work. and will it make much difference to power? will i loose or gain some?

 

If you've gotten it to run perfect it shouldn't smell too strong. The converter will help burn some of the unburned fuel but not to the extent that it will cure a problem that can be cured with better jetting and or timing. Most of time I have experienced people are jetted too rich and are especially rich at idle to 1/8th throttle. This can be caused by wrong sized jets or even a float level that is too high causing raw fuel to go into the intake. Also make sure your are running proper pressure from your fuel pump. I have a great mechanical pump and I still run a regulator to only 6PSI.

The converter will not gain power, it can cause a slight (very) since it is a honeycomb structure that impledes flow.