BigLar11
New member
Well you have to have the downpipe on before the tune.
If you do the downpipe way in advance and drive for weeks and thousands of miles, you'll probably eventually throw a code. Chances are it will be a P0420 code. You can still drive the car but you'll need to get 02 spacer(s) to pull the sensor out of the gas stream a bit to trick the sensor. If you have emissions testing you will need to do this. If not then you can just set to stage 2 and drive as it will turn off the CEL for emissions.
Do you think it be best to get the downpipe and install it closer to when I get the tune (in July)?