Can someone explain the relationship between torque and horsepower ? I have owned F250 Heavy Duty / superduties for 20 years and have had an assortment of gas V8's and most recently my 2001 has the powerstroke diesel. It seems like the gas engines have high numbers with the horsepower but score lower in torque. What makes the diesel squeeze so much more torque out of seemingly less horsepower. I think my 1994 F250 with the 5.8 litre V8 was rated at about 245 HP and a little over 300 ft/lbs. on torque while the PSD is similar on HP with over 500 ft/lbs. on torque. At first I wrote it off to the fact that the PSD was bigger at 7.3 litres, but now the new PSD is only 6.0 litres and exceeds the 7.3 in both catagories! On the extreem end, racecar engines have incredible HP but I'm guessing probably couldn't pull much of a load. Thanks in advance for your comments!

 

jskufan,

I had the same question a while back.

http://auto.howstuffworks.com/question381.htm

It will explain alot.

 

Thanks for the great link, I saved it in my "favorites" folder. My brother has a Cummins 5.9 in a 37' RV and he and I are always debating topics like this. Thanks again for your help.