i checked air pressure and the max on my tires is 50 so i put in about 35-38 (they were at 20-35 varying from tire to tire)

Check what's your recommended tire pressure if the tires are same size as stock, not just guessing. Right tire pressure gives you better mpg, not more/less.

Any if your wheels only cost like 3-400 to begin with, you are better off getting new ones.