[tjl]

This looks seriously unpleasant and unsafe for any driver going the opposite direction when encountering you on the road.

 

[tjl]

It is NOT legal to modify your catalytic converter in California, which is what you have to do to to add a turbo.

Not necessarily. There are some CARB acceptable aftermarket turbocharger kits or modifications, as well as CARB acceptable OBD-II and non-OBD-II aftermarket replacement catalytic converters:

Database: Aftermarket Parts Database of Executive Orders