I think it will have some affect, but it shouldn't be that dramatic. I am on my 2nd 5-speed disco. First one was a stock SE7 with 255/70/16 tires(bigger than stock). I got 13-14 with city driving, and 17-19/20 on the highway. That is going 67-70 mph. No lead foot here people!
The second one is a 96 as well, with a 4inch lift. 32" tires. I get @12.5-13 combo driving. I havn't checked it on the highway, but with a full rack I got about the same at around 65mph. I have noticed that O2 sensors on there way out will kill your gas milage too. I had a check engine light come on, and then turn off later. The stored code was an O2 sensor problem. Mpg dropped slightly after that. Run some techron cleaner through it, and take it on a long drive. Get that carbon out the engine. This will help things drasticly. Techron is good for gas treatment carbon issues. Seafoam is good through the plenum, as it is most effective that way, but it will help through the gas tank. Let me know how things work out!
**BTW. you could STILL have a code without the CE light on!!!**
__________________
Eric The Red
93 Range Rover Classic
We will never "arrive" so the goal is to keep moving forward on our journey so we can periodically declare, "I am not what I want to be, but I am not what I used to be!"
96 DISCO SE7 5-SPEED SOLD
....okay
couldn't live without a disco!
96 DISCO SD 5-SPEED
-ARB Bumper
-OME 2" Lift
-2" spacers
-Safari snorkel
-15" steelies
