Posted by Jim on August 16, 2000 at 03:38:18:
In Reply to: Shifts posted by Polar Pilot on August 15, 2000 at 16:06:13:
If I may be so bold as to answer for PolarPilot, I think he was getting at this:
In 5th, the RPMs are lower (so in the sense of pure "revs" the engine is not working harder) but the tranny is now geared so that the wheels are spinning faster than the engine is cycling. This makes the engine economical (less rotations = less powere strokes = less gas), but not very powerful. At high speeds, the engine is essentially justain maintaining momentum, so it doesn't have to "push" very hard, just enough to keep spinning (picture spinning a basketball or frisbee on your finger: once it's up and running, just little "boosts" keep it spinning). The downside is that if you demand power, their is more stress on each powerstroke to give it. Hence Polar Pilot's statement that the engine works "harder" in 5th. This is why we downshift to pass, climb hills, pull heavy loads, etc....
Hope this made some sense.....
-KTRSD
-Jim