This is notable. The Hellcat runs around 1950 or so at 60mph with a manual transmission, which I always regarded as rev overkill. It needs a 1.91:1 rear end, in my opinion. Then I could run a Lenco (which only does direct drive as its top [lack of] ratio, and still get reasonable fuel mileage I did a huge, elaborate spreadsheet to find what engine speeds/mph I could get with a Lenco with various ratio selections, but the lowest revs I could get would involve a 2.62:1 rear and they still weren't low enough to get decent mileage compared to the stocker. (I put no upper limit on the number of actual ratios/levers.) I don't like the idea of motors that get big torque at 900RPM screaming along at 2000 RPM, unnecessarily.
The inefficiency of those was largely due to the wasteful, sloppy, non-lockup torque converters of that time. The Challengers use a lockup converter, to my knowledge, so their low revs on the highway translate more directly to better fuel mileage than the manual-transmission versions, which turn at a higher RPM at the same highway speeds than do the automatic-equipped versions due to not having enough gearing to drop the revs as much as the automatic trans/ 2.61 rear end ratio cars.
It cost $8 to fill the fuel tank when that big caddy engine was released. It was about 500 HP, and 535 TQ. Over the years the EPA neutered it so bad, it was only putting out about 200 HP. But you have to watch the 10 minute video. The narrator is good to watch around nap time. Challenger, and better fuel mileage? LOL! Mine drinks like a fish.
My Hellcat gets around 20mpg highway. The Automatic is a bit higher at 22mpg, I've heard. Curious why yours gets bad fuel mileage. What's the rear end ratio? How many RPM at 60mph?
I get about 18, mostly drive in town, and rural roads. I have MDS turned off. 3.09 rear end, not sure of the RPMs. The window sticker claims it's capable of 25 MPG, maybe in Eco mode, but I have that turned off totally. I didn't buy it for the mileage, just thought it was funny you would mention MPG on a car like this.
I am very engineering-minded. I even wonder about the aero efficiency of the underside of the car. It's a game I like to play with almost anything.
