Bedlam wrote:
That's been my experience too. When I had a little 4-cylinder gasser pickup, I could get 25 mpg when empty while driving over the mountains but was in single digits when towing 5000 lbs. This was an engine with 121 hp and 149 lb-ft which by your explanation should have been getting better mileage while towing because of the limited power it created.
That reminds me of the Top Gear UK mpg test they did a while back where they put a 1.4L 4 cylinder Prius versus 4.0L V8 BMW M3. They ran a Prius around a road track 10 times at the best it could run and followed it with a BMW M3 essentially using the same hp for their weight and drag. The BMW got more than 2 mpg better than the Prius. The track was not a high speed track so the BMW did not benefit from any drafting.
BMW M3 vs Toyota Prius
