I think the stock duelers are recommended to be run at 29psi. I run them at 33 though. you could try drawing lines across the tread of your tires and see how they wear to find the best pressure to run them at. If the line wears out of the center first, you need less pressure, if it wears on the sides first, you need more pressure. as tom said, the lower your pressure the worse your gas mileage is, the higher your pressure is, the harsher the ride will be