I can't be 100% certain, but I will keep this thread updated. When I first got my car running with the 3L, I was running 19# injectors and the stock SVT throttle body. The car was 100% untuned, but I was getting 25-27mpg mix of city/highway. I'd be at 200 miles right when I was at 1/2 tank. When I installed the 64mm T/B, it seemed to kill my gas mileage. I didn't keep close records at that time, but I also installed the 39# injectors, and got the Xcal2 tune. Well, I was getting between 18-20mpg with the same driving habits. I would then be at ~160miles to the tank when I was at 1/2 full. I had almost ALWAYS gotten my gas at BP, using their 93 Octane Premium fuel. Well, I thought I'd give Shell a shot this last tank. Filled it up with their V-Power 93 Octane, and I just got to 1/2 tank with 196 miles!! I'm going to see how many miles I get to the tank, so I can be a little more sure. But this is the only thing I can attribute to the better gas mileage. Unless the old 65mm T/B I was running that had an air leak, was causing that much of a decrease in MPG. Anybody else using V-Power from Shell, and notice a difference?
Mark
