thats a good question bubble boy. Im not sure if a completely stock diesel would be able to beat a stock gas job, assuming you are putting it up against a same brand. For instance, chevies big gas motor is pretty powerful and would probably beat the 300hp duramax. Now a non stock diesel can blow that away. In my truck i have a 4 inch exhaust, computer and intake, and will blow the gas out of the water. You wouldnt beleive the power you can crank out of a diesel with a few simple mods.
"Lifes a garden, dig it"