351W Gas Mileage & Dyno Tune

Hi there, I'd like to know what some of you Torino/Fairlane/Ranchero people are getting for gas mileage with a 351 Windsor. My Ranchero engine used to have a two barrel Holley carb but I changed it to an Edelbrock AVS 4-barrel on an aluminum intake. It used to get around 10-11 miles per gallon with 92 octane gas but now it gets about 15. Just wondering if that's about normal, better, or worse than what other people are getting.
I also recently had my truck dyno-tuned, and the horsepower at the crank was 268.1, and the torque at the crank was 392 ft/lbs. On a pretty much stock engine. So also if anyone can comment on that it would be great... thanks.

Lauren