can't find replacement converter for car GM not making at this time been in dealer ship since Nov. can the converter be reemed out and reinstalled or will removing the back pressure cause low power from engine
Your vehicle is tuned to have a certain amount of back pressure. Hollowing out the cat, however, will have a minimal effect on engine power. If you decide to remove the catalytic converter's inner mesh, you will encounter a check engine light for a failed catalytic converter. You can fix this by buying a 90 degree O2 sensor spacer, and installing it along with the sensor on your downstream (after catalytic converter) O2 sensor socket.
Oh, and fun fact, engines don't need back pressure. That's a myth.