Hey guys,
I am debating on what to do to my exhaust. This is what I have now. Ive got a 91 RS with a 305 TBI/auto. Its got Edelbrock TES Headers & a Flowmaster Cat-Back. The car sounds GREAT.. Most of the time. My problem is the catalitic converter.

The converter on the car is the stock one. I know that its shot because the car has over 120,000miles on it & I am failing emissions. Also, the cat has a leak in it that sounds LIKE **** at certian RPM's. Usually when the car shifts into drive or overdrive during light throttle, you can REALLY hear it. Anyway, I already bought a 3" Magnaflow Cat from E-Bay. Unfortuneatly, I bought a 3" cat were the pipe that it needs to be welded to is only 2-1/2" These are my options:

Return the 3" cat, get a 2.5" cat

Just use adaptors to make the 3" cat work

Return the 3" cat have have the exhaust shop do a custom y-pipe with 2 cats.

 

Is your cat-back 3". I am not sure if all of the flowmaster ones are. If it is then use the 3" cat and have an exhaust shop weld on a reducer to attach to your y-pipe. If you got the TBI specific hedders from edelbrock than your y-pipe should be 2.25" if I am not mistaken. Here is a pic of my reducer welded on to attach to the Blowtech 2.5" y-pipe.