Hello Scotty and community, 

I am concerned about my 1989 Nissan Sentra (122,211 miles) not potentially being able to pass emissions testing and I think California does not exempt this car from smog testing unless it's 1976 or older. What do you (all) recommend to help better increase the chances of passing the smog test? I just found online records of past emissions testing from the California Bureau of Automotive Repair (BAR) for this car and last smog test was in 2017 and passed at that time. I know It sounds silly to emission test such an old car, but I plan to only use this as my pleasure car learning to drive standard as the car is equipped with a 4 speed transmission. 

How different is emissions testing for OBD-1 cars than compared to OBD-2 cars, and is OBD-1 emissions testing still available to test older cars? 

The car is currently in the mechanic shop, almost done with repair (hopefully) after an used JDM engine transplant (original engine has bad crack), new front CV axles, radiator, distributor, spark plugs and wires, etc. (I'm itching to go pick up my car when it's ready.) I bought 4 brand new Douglas P175/R13 13 inch tires at Walmart for $35 each to plan to replace the deflating, cracked, and balding original Michelin tires that are currently are on the car. I also bought a new Nissan OEM oil filter, FRAM fuel filter and new air filter. What else should I do, drive the car around in the neighborhood with help of a friend knows how to drive standard to get the catalytic converter working? Check Mass Air flow sensor if it has one? Engine is a Nissan GA16i 4 cylinder 1.6 litre fuel injected engine. Car is not road legal yet has expired 2018 tag. Thanks in advance.