Been reading a lot and getting some mixed info on stuff.
I replaced my kegger with the ai air gap to fix plenum. Distributor cap and rotors also replaced. Wires and spark plugs were just replaced as well a month before plenum. Radiator and 180degree thermostat were replaced
Does the cat and o2 sensors also need to be replaced?
Also I have a magnaflow dual exhaust should i also switch the exhaust manifold?
Trying to improve mpg since the new air gap doesn't seem to be at its full potential.

Thanks,
DF

 

If the O2 is old, it could probably stand to be replaced. They don't last forever. Go with a denso, or NTK. Skip Bosch.

Do you still have cats? Or do you now have two cats??

 

replacing the cat and o2 sensors definitely won't hurt anything...if anything, it'll only help. Get a high flow cat (magnaflow or flowmaster) and I think you'll like the tone it gives the exhaust. I just replaced both sensors and the cat on my 01 and I gained back another half mile per gallon (up to 11.0 mpg according to my on board computer...which is slightly on the low side because i'm running 33" tires so the speedo/odometer is a little off)...not much but every little bit helps!

 

1 cat it's already upgraded not stock but I didn't do it. It was replaced over 4yrs ago by previous owner