What should I do next for better mpg?

[PA32R]

Originally Posted by ibetyouluvthis

I drive a 2005 corolla.

+I switched to synthetic oil. Castro Syn 5w30. Should I use a better brand?Grade?
+Cranked up the psu on the tires. 38psu
+Changed the spark plugs-which would be best formpg?Platnium?Iraduim?othr?
+Replaced engine filter with K&N drop in. Was this a good idea?

What should I do next? I'm new to this forum. Give me some ideas. I"m new to this forum.
Any suggestions aprreciated

Thanks in advance

Are you new to this forum? Sorry, I couldn't resist I haven't been here all that long myself, only since April, but welcome.