1997 1.6 liter engine 3 speed automatic tranny( wish I had that 4th gear) 293 mile trip 65-70 MPH with AC on 100% of the time. Half flat roads half hills. Also includes about 1 hour of stop and go traffic as well as about 80 miles of local driving. Net result was 38+MPG. The only time I ever came close to this was 36.8 MPG doing 55MPH on flat terrain. I'm certain I would crack 40MPG at 55 and no traffic! I have an EFIE installed and MAP sensor enhancer. HHO at 1 LPM at 20 amps. My Pelican case has held up perfectly with no issues. I'm figuring on about a 25-30% increase in MPG conservatively. The EFIE is a MUST for these results, on my car anyway. Finally some progress!!!!