Does anyone know how much air pressure you should run in a 225/40/19 under normal driving conditions? All I see is a max pressure on the tire. Can't find what pressure I should be running.

 

sedan or coupe?

coupe use 35-36.5PSI

 

open your driver door and look on the door jamb. This is the proper tp for the factory sized tires. The sidewall does not carry the weight of the car, air pressure gives the tire the proper load capacity based on its size and the weight that it need to carry at each corner of the car. A couple of lbs each way will cause premature wear on different parts of the tire. A couple of lbs each way for short periods of time for draging or tracking is ok. When its hot under pressured tires will get overheated and can cause tire failure. Too much pressure makes the car jittery. I know thats more info than you asked for, just like trying to help

 

It's a sedan. I can't look at the door because these are aftermarket wheels and tires. Sedan does not offer 19" as an option.