After being sidetracked for 6 or 8 months, I'm doing some fabricating for my 100 mpg tests. I was also thinking about a second test vehicle and my neighbor has a VW van for sale. I want to heat the air intake charge to about 220 degrees. I was thinking about the VW's air cooling and the great source of heated air it could provide. Does the fan draw air across the engine or blow? But about the previous post. Someone was commenting about air cooled engines, and the opposed 4 cyl, giving the VW as an example. If I remember correctly, the comment was to the effect that they weren't the best design for efficiency and high mileage.