ZenRockGarden
Active Member
US EPA tests should use an 80 MPH highway cruising speed, and even that is slower than a lot of traffic flow. But basing the ratings on 80 MPH would provide a much better set of real-world numbers, especially for EVs which get worse mileage on the highway.
80 is the highest speed limit in all states except the parts of Texas that allow 85 MPH. 70 MPH is the max posted limit on the PA Turnpike and if you're doing 80, a good portion of the traffic is going faster than you.
The EPA does have a "high speed" test that touches 80 MPH, but it is not used in the calculation for official fuel economy numbers