Hey, i have a 1992 Sedan Deville with a 4.9 TPI V8, i averaged about 13.6 mpg on premium, but now i am getting about 15.2 avg. I was wondering what you LT1 Fleetwoods average with about 900lbs more car. In my LT1 Roadmaster i got about 13.7 AVG MPG with 147k miles, and i drove it kind of hard, and mainly city driving, plus i'm not sure how good it was running. I bet
if i had new plugs, and stuff i could average 15, Is this reasonable? What do you guys average with any fuel injected 350? Is the TBI version much worse?