Got 83mpg cruising down the interstate at 60-65mph?.
Got my best average mileage so far (83mpg) for the interstate portion (I-26 from Weaverville, NC to Flat Rock, NC) of my commute going home. Roads were dry, temp was 75F with no significant winds, and with a moderate amount of traffic. I was running at the speed limit to 5 over for the most part, with the speed dropping a few mph on the uphills and going 5 to 10 over on the downhills (with a Cd of 0.17, I gain speed quickly on the downhill despite driving a 2100 lbs car).
I was helped out on this trip by being followed by a panel truck towing a car that was taking the uphills at a leasurely pace which allowed me to drop my speed a little more on the uphills than I normally can given the traffic conditions. I normally get 77mpg on this stretch of highway. Who says you need a hybrid or diesel to get good mileage.
Perhaps the poster is a motorcycle/scooter user? Although it's not unheard of in small diesel cars, it's very difficult to achieve in a petrol car. My best was 97.2 MPG which is 80.9 US in my Renault Clio diesel, but I had to employ hypermiling techniques to achieve this.
Edit: OK I read it again, they're in a car, ignore me haha