# Thread: K75 Power/Torque Band Graph - Fuel Consumption

1. ## K75 Power/Torque Band Graph - Fuel Consumption

My knowledge of the German language is essentially nil. However, I would think that the left side of the y-axis graph below refers to Horsepower and the righthand side refers to torque. The x-axis is obviously RPM.

From the K75 power/torque graph below, would the lowest fuel consumption occur at the 4500-4600 rpm or where the torque and power curve intersect? Also, is there something to be interpretted from the 6750-6900 rpm range where the delta between torque and horsepower increases? Is that the point where one gets the maximum from the K75 engine per unit of fuel?

2. Many decades ago, my Volvo mechanic told me that all internal combustible engines have the best mileage at 60mph. Don't know if it's true or still true, but I do know that I certainly get better mileage on two lane roads as compared to interstates with higher speed limits.

3. Originally Posted by Paul_F
Many decades ago, my Volvo mechanic told me that all internal combustible engines have the best mileage at 60mph. Don't know if it's true or still true, but I do know that I certainly get better mileage on two lane roads as compared to interstates with higher speed limits.
That's an interesting thought Paul, as the 60 mph or 100 km/h on my K75S is pretty close to the 4500 rpm range, if memory serves me correct. We just got dumped on by a foot and an half of snow, so I can't verify anything right now.

ghyber

4. ## HP/Torque Curve Explanation

Kevin Cammeron has explained this the best I've seen. He writes for a leading motor mag. I recall that he said the HP/Torque charts "always cross at the same RPM because of the math involved"

Here's a link to part of one of his books: page 46 is what you ask about