Quote:
Originally Posted by 43Supporter
Hmm - our interpretation back-when was:
"Effectively doubles PFs for purposes of maximum load the vehicle can carry or pull, not maximum speed or mileage." [CWC 2.5 p 113]
Max. speed is determined by Power Factors; if HD Trans doesn't affect top speed, it therefore does not affect the PF count. ("Carry or pull" is a bit confusing, as a load on a trailer could be classed as either.)
|
If you argue that HDT "does not affect the PF count" then it can't tow extra weight either (compare rigs). I can see what you mean though, power is work done over time and you are not changing that with HDT, you are delivering more work but taking more time to do it (lower Acc, lower top speed etc.). Whilst PF chimes well with HP (the usual means of describing vehicle power), we are considering different gearing as well with the HDT and the default CW speed calculation takes no account of gearing, just raw power.
That said my reading of the sentence highlighted (and that used by others in their vehicle design software) is that you always use the plant's
base PF in the speed and range calculations. With HDT however you are now applying it to a vehicle that potentially weighs 6 times the PF (rather than a maximum of 3 without HDT). This generally means your top speed is about 55 mph at max loading. A non-HDT vehicle with a plant at max load tops out at around 90 mph. This has a knock on effect on range.
Whether that extra load is on the chassis or a trailer is immaterial.