I shoot a 260 with the 140 amax at 2800FPS
My buddy shoots a 7-08 with the 162 amax around 2700
Mine shoots a tenth or two of a mil flatter out to 1,000. Beyond that the 162's start to pull ahead.
This is real world shooting next to each other observations.
The 7-08 hits harder but I've dropped a few pigs in there tracks with the 140's.
As has been mentioned you can get the 162 out of the 7-08 faster than 2700. If you want something else to consider using the two speeds RRFLYER mentioned in his post look at this:
Wind drift 1000 yards with a 10mph 90* wind
7-08 (162amax) .77mrad
260 (140amax) .88mrad