Quote:
Originally Posted by bwilson4web
Hi,
Some of us in Prius_Technical_Stuff are looking at ICE thermister circuits that will allow NHW11s and possibly some NHW20s to achieve S4 operation quickly and avoid falling below the S4 mode in slow-speed, cold weather operation. However, it is a work in progress.
http://hiwaay.net/~bzwilson/prius/pri_temp.html
BTW, one of the other members is doing some experiments with pre-heating the intake air. The theory is this accelerates ICE warm-up and the less-dense air reduces pumping losses. It is an experiment in progress.
Bob Wilson |
Thanks for the excellent and detailed posts. As I am not a hypermiler (and will likely never be due to my driving requirements) a good deal of this is over my head. However, it is quite helpful in allowing me the opportunity to see what impacts my driving "style" may have on my overall FE. Basically, what the data (and your responses) seem to indicate is that once the ICE has been engaged, either above or below 42
mph, the impact to my fuel economy is the same. The best case scenario I can achieve at that point (assuming I can’t simply glide to slower speeds) is to maintain a yellow arrow to the battery as often and as long as possible. It also seems to indicate when the ICE is engaged my best FE will occur when I remain below 40
mph or above 45
mph consistently. Hovering between 39 and 45
mph means I will run the risk of turning the ICE on and off frequently, thereby reducing my overall FE.
Also, as I reviewed the link above, it was interesting to note the key temperature thresholds of 40C (100F) and 70C (160F) where the ICE may shut down based on the demand put on the ICE. Given these hard wired thresholds, it would be nice to have a temperature gauge as part of the standard equipment in a Prius. It would certainly allow the driver more specific data in attempting to manage their FE numbers.
Thanks again for everyone’s responses.
UTpiper