Massaging XJ fuel economy (long)

[Menzenski]

96, manual, 30 tires, stock 3.07s, K&N filter

Mixed city/highway driving I get 15-16 mpg. I usually drive aggressively. I have dramastically changed driving styles to see the impact on economy. Same result 15-16 mpg. How I don't know. I have tried shifting at 3k, slow acceleration, fast acceleration, and dog a$$ slow. I used the same gas station, same driving conditions, and the same route over multi fill ups. Always consistent. riddle me that?

Consistent 75-85 mph highway driving, I am able to get 18-19 mpg.

I still wish I had cruise control.

I've got 31s on 3.07s, and I get just about the same mileage. After I replaced my clutch (a little over a month ago), mileage jumped from about 14 mpg to about 16.5 mpg. Highway, I've averaged 18-19 as well. I really drive like a grandma though (never over the speed limit, et c.).