4 banger Gas milage?

I Have a 1993 YJ 2.5 liter with only 120,000 miles on it. It's mostly stock aside from an add a leaf suspension, and 31" BFG A/T KO. The other day I calculated the MPG it was getting from it's 13 gallon tank & it came out to be at most 11.7 Mpg. Now I understand that it's a jeep and I'm not looking to have outstanding gas mileage, I just don't understand how my milage could be low while there are other YJ's with more mods and bigger engines getting better than mine. I've recently replaced the fuel regulator , fuel filter, had an oil change, and I also have 19lb injectors with 4 jets, from a Lincoln continental. It's mainly used to get to school and work, and It doesn't see to much off-road action atm, so most of the miles are highway. I try and shift low at around 3000-3500rpm, but I can never start from 2nd gear or it bogs out.



Does anyone have any tips, tricks, or things that might be worth taking a look at? All advice is appreciated, thank you!