Hey, I have run both on my 96 civic, the cold air had more pull to it, but I found it best to pull the second pipe off and run the short ram in the winter. My gas mileage did not change at all with either one. I would suggest using a K & N filter, the cheap one did not so a very good job, and my oil was nasty even at 2000 miles. If you run a full cold air, don't forget to install a by-pass vavle from AEM, it will save your engine on rainy days.