All good points. The end result, in any case is to place the engine at the ''sweet spot" as much as possible, even on the heavy haul big rigs.
If running a small engine at speed to run a generator worked, surly someone would be doing it now. Why not? Grant... AZ.... On Fri, Nov 18, 2011 at 10:14 AM, Fmiser <fmi...@gmail.com> wrote: > > G Mann wrote: > > > That would be 28 Peak HP.... so you need those 18 gears to > > keep the little engine exactly in BOTH it's best torque and > > best Horsepower sweet spot to gain max efficiency to achieve > > that "perfect" mileage. > > And if the only duty of the engine was to run the generator that > powers the electric motors it _would_ be running at exactly it's > sweet spot. > > And then, just to pick at nits, *smiles* there is hardly any big > trucks on the road with an 18 speed transmission. The 18 speed's > primary duty is for off-road service. 9 and 10 speed are the > most common. It's not rare to find a 13 speed, and a 15 speed, > though unusual, is not unheard of. > > Since I'm on this rabbit trail already, I'll continue... > > The RoadRanger type transmissions used in the big trucks today > are a 5 speed main gearbox with auxiliary gearing. Using air > pressure from the air brake system, there are "switches" on the > shifter that operate "solenoids" to change the auxiliary gears. > It can be a large ratio change (range) or a small ratio change > (split). > > 9-speed = no splits, 5 in low range, 4 in high range > 10-speed = no splits, 5 lo, 5 hi > 13-speed = 5 lo, 4 hi with splits > 15-speed = 5 lo with splits, 4 high > 18-speed = 5 low with splits, 4 high with splits > > -- Philip > > _______________________________________ > http://www.okiebenz.com > For new and used parts go to www.okiebenz.com > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
