Is it carbed, throttle body injection, or turbo with port injection? Hopefully its not carbed.

87 could have had any of the 3 inductions systems. By 87, most of the emissions were built into the systems, messing with the systems usually resulted in a very poor running car. I was a dealer tech in 86 & 87. The biggest issue we had (outside of head gasket sealing) was people that tried to remove the emissions, and the gas with higher then 10% ethanol content.

By 87, the carbs were really bad, very poor quality with lots of issues. The best upgrade was to replace everything (intake, wiring, and computer) to at least the throttle body induction system. The carbed motors originally had a mechanical fuel pump, if it still has one of those, you really need to step up to the in tank electric pump. Back in the day, there was a drivability kit to make that changeover, but I suspect that is no longer around. If there is a carb, you have to absolutely make sure the gas you buy is no more the 10% ethanol, or the carbs won't work worth a crap. There was a whole host of "drivability upgrades" that came along on the carbed motors in the 86-89 era, to make them acceptable to drive correctly. If you car is carbed, I suspect some (most?) of those things you think may be "smog" stuff could well be drivability kits that have been added so the car drives OK, but I don't know how much more stuff was added for CA emissions. We re a long way from CA.

The throttle body injection added about 10 more HP to the motor, and you could feel the difference. The throttle body systems were 10x better with driving issues then the carbed versions. Removing any emissions stuff will kill the drivability, reduce the fuel economy, and kill the power levels on them. Everything was designed into the system, and it actually worked pretty well.

The turbo 2.2s were pretty much fun, but were not often ordered on the Duster/Turismo line. They were a huge upgrade from the throttle body injection Gene