According to the Tire Rack specs, the maximum inflation rate listed on the sidewall of that tire is 44 PSI. So if you're going for a little extra fuel economy, you could always increase the pressure close to that level.
Also keep in mind that you just went from a worn-out Low Rolling Resistance tire (which has its least rolling resistance when it's worn out) to a brand new non-Low Rolling Resistance tire. New tires have the highest rolling resistance when they're new. So it's no shock if you are noticing a slight drop in fuel economy.