While comparisons are being made between diesel and gasoline I think people might find the following facts interesting:
Diesel contains more BTUs per unit of volume than does gasoline, but, gasoline contains more BTUs per unit of weight than diesel does.
Because gasoline requires less air to burn than diesel does, gasoline engines produce more torque than do similar displacement naturally aspirated diesels do. It is the turbo that is responsible for the high torque value of the modern diesel engine not the fuel type....diesel engines lend themselves to turbos more so than gasoline engines. The direct injection (such as the eccoboost) engines are begining to change that. So potentially a 6.7 turbo gasoline engine could produce more torque and much more power than a 6.7 turbo diesel.