2001 honda accord vtec 4 cylinders?

I just bought a 2001 accord a couple of weeks ago and before that a had a 2001 dodge neon v4 well my question is why is my accord less fuel efficient than my neon? I never looked under the hood and today I did and I discovered that my Honda accord has a 4 engine and I thougt it was a v6 cause of the gas mileage I get. my neon was way better on fuel, I had accords and civics before they were the best on fuel efficiency but they were not vtec is that why? I have new plugs and wires new oil, new air filter do I need anything else?