Awhile back someone asked if I got an increase in fuel mileage with my Spintech muffler system. My response was that I had not been on a trip yet to see. Well over the long weekend I went from 50 miles east of Los Angeles to Moro Bay. I made this same trip at Christmas time. In December I got 16.9 MPG in my 2000 Expedidtion with a 5.4L. The trip over this weekend I was getting 18.5 MPG. Over a mile and a half more per gallon. I put the system on for increased torque to tow and to have a nice sound. The increase in MPG is an added benefit. http://www.spintechmufflers.com

 

I not saying this to flame you. I know in some areas the winter gas is difference than summer gas. They put something in the winter gas and that will cause yuor MPG to go down. I'm sure that the exhasut did help though.

 

i've never heard of a muffler increasing gas mileage. maybe it does. if it works for you, great. i'd still have to experience that to believe it though. Rich.

 

King James: you must not have read my profile. As an ASE Master Auto Mechanic let me get technical with you. You are right. Many parts of the country do reformualte their gasolines. They oxygenate them. If you are a jet mechanic you know that more oxygen means more power not less. Drag racers use NO2 to get more power. The Nitrogen is what expands to push the piston down and the oxygen is used to make the flame hotter. This means the fuel in the winter makes more therms per molecule than the fuel in the summer. So my mileage with winter fuel would have even been more of an increase than what I got during the summer.

 

I understand your reasoning. I know that in the winter the air is denser so the motor doesn't need to spin as fast to produce the same amount of power as it would during the summer. I heard that the winter fuel has a lower BTU rating. If that is true, I don't know.

 

Your are right again. Engines don't spin as fast. The reason is you drive slower in bad weather. Slower to a point of inefficiency. This is what causes the lower MPG. Here in the Los Angeles area just a spit of rain sends everyone into a frenzy. An hour drive easily turns into a 2 1/2 hour drive. They oxygenate the fuel to get the Carbon Monoxide levels down. People are stuck in their cars and in their homes and where they work and the carbon monoxide levels rise causing health problems. This is one of the emmision standard blends they say is causing fuel prices in California to be so high. Funny thing is many other states use this blend all the time. I was in the midwest a couple of years ago and was getting 3 miles a gallon better mileage in my little Ranger on a trip in July than what I started with out here in California.