Quote:
Originally Posted by JamieGeek
That is easy to "fix" without a 5-Star...you just have to pay attention.
When driving our Axis on cruise control and approaching a hill/rise/grade/etc. I'll just tap the gas pedal just enough to force a downshift right at the bottom of the hill. The cruise will then hold it in that gear up the hill without it dropping much speed at all.
|
The other easy fix is to change final gearing so that engine normally runs at higher RPM, lower Brake Mean Effective Pressure (torque), and thus has greater reserve power during normal conditions.
In the example I gave above, if final gearing is changed so that the same 100 HP was at 2,700 instead of 2,250 RPM, then torque would drop to less than 50% of available. That means that the same 2% grade that increases required power from 100 to 150 HP would increase torque from <50 to <75% of available. And since 75% torque is very manageable, the transmission could remain in top gear.
The main problem is that the engine running at 2,700 RPM and about 50% torque will burn a little more fuel than at 2,250 RPM and 60% torque. That’s basically the way vehicles were geared decades ago, which made frequent downshifts on rolling hills not as necessary.
I suppose that when we are all driving electric cars and RVs with one fixed gear, there won’t be any shifting complaints.