View Single Post
Old 10-19-2017, 12:29 AM   #18 (permalink)
Join Date: Jul 2017
Location: Wisconsin
Posts: 48
Thanks: 20
Thanked 8 Times in 5 Posts
Originally Posted by puddleglum View Post
I think I understand what you guys are getting at, but I'm sorry, I respectfully disagree. I would have to see some empirical proof to believe that. It goes against the whole concept of driving with load which is a well accepted practice. "As far as the amount of energy it takes to climb the hill, it doesn't matter how fast or slow you do it." That's wrong, speed is a primary component of acceleration. Have you ever ridden a bicycle up a hill? Go try riding riding up a steep hill in high gear at the same speed you can ride down hill. You'll be exhausted. If you slow down and use a lower gear, it's not that tiring.
Granted, speeding up to 80 going down hill is a waste because of wind drag. But, say you want your avg. speed to be 55 on a road with lots of hills. If I understand you, your saying to start the climb at 50, accelerate (pulse) up the hill to 60 and coast back down the hill, dropping back to 50 before the next hill. Driving with load technique, says start up at 60, dropping to 50 by the top, then pulse back up to 60 on the way down. I'm pretty sure DWL will use less fuel than your method. If you can show me some data that proves me wrong, I'll gladly recant.

Now everything is situational as has been said already. In some situations I will accelerate up hill and coast down as well, but, it really depends on the specifics. I agree it may be more efficient in some situations but not as a general rule.
It is literally not situational. At all. As has been said already.

I work in powertrain engineering, and I can give you data like it is coming from a firehose. It will benefit you to first understand the concepts that cause this phenomena. The efficiency curve of a spark-ignited gasoline engine is important to understand. Its also vital to understand that wind drag plays a major role.
2007 Silverado 1500 2wd flex fuel with active fuel management. 33" Nitto Terra Grappler tires. 2.5" motofab front end leveling kit.
  Reply With Quote