cummins 450 hp

[vett]

on a cummins 450 hp can some one tell about rpm's to torque or power band to speed going up hills
thanks

[BrianGlenn]

Small torque curve located in this brochure.

Clicky here ISL9 450 for RV applications. 2010 vintage so possible some changes since then.... ECM version, possibly some minor tweaks to mechanical components, etc; may change shape of curve but probably similar peaks in new engines.

Speed going up hills is dependant on way too many factors to compare across coaches; gearing, GVW, grade, air temp, etc, etc, etc......

Brian

[select55]

Originally Posted by vett

on a cummins 450 hp can some one tell about rpm's to torque or power band to speed going up hills
thanks

go up the hill in whatever RPm that will hold your coach at or near the speed limit. if your in #6 and your to the metal and loosing speed then you best gear down a notch and so on ;;there is no magic formula per say
some hills u will fly up and some u will be down to 45MPH and at 45MPH you will be in 4th gear and 2200 RPM

[Steve Ownby]

Originally Posted by vett

on a cummins 450 hp can some one tell about rpm's to torque or power band to speed going up hills
thanks

The torque/hp curve depicted in the above post shows torque max occurring at 1400 rpm and peak hp at 2100 rpm so that's your effective power band. Climbing performance requires keeping your RPMs up as close to the hp peak as possible. In practical terms, that means you manually downshift the Allison at the start of the climb to get your RPMs up above 2000. As you climb, as your RPMs fall, downshift again to get back above 2000. Your Cummins is governed at 2100-2200 rpm so you can't over speed the engine. At some point, depending on the length and degree of the climb, you will be in a gear that will enable you to maintain your target rpm. This technique will also keep you engine temps down.