Join Date: Apr 2008
Location: Grass Valley, CA
Re: Better mileage-intercooler or water meth
Well, the water/meth will make you use less diesel, but that's because the Methanol will be a second fuel. you have to consider it's cost to be realistic about your mileage as well.
honestly, I'd do a bed cap and air dam (even if it's smaller). If you're honestly doing 20ish now, that may get you to your goal.
Also, I would think your smaller exhaust housing is going to increase your EGT's and backpressure and not really be a benefit.
96 Powerstroke: 6637, downpipe to dump exhaust, 140v IDM and a shift kit.
84 Honda Sabre V65 1100: pipes, jet kit and new tires. Faster than I think I'll ever need.