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Discussion Starter · #1 ·
Hello, I thought some of you may find this page of information interesting:
http://www.allpar.com/mopar/new-mopar-hemi.html:
"... Fuel economy gains go up to 20 percent under various driving conditions, with a 10 percent (or so) aggregate improvement, without any change in customer experience—drivers will receive the benefit without changing their driving habits or losing power."
;)
 

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I hate it. I rarely drive in the conditions that DC claims it is in use. I wish they just kept it a Hemi. I don't mind it, unless it ends up causing problems in the long run.
 

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Discussion Starter · #3 ·
Jangy, since we both have science backgrounds, you know as well as I do how to "manipulate" numbers, but do not be so overly pessimistic ... the the law of averages (even with your driving style) will eventually benefit your gas consumption. Every time you take the foot of the gas pedal and coast (let alone brake) and within their allowed v-range) will save some fuel. On top of that, I use cruise control as often as possible to save even more ... the only way to stay away from tickets for me ;). Do I go out of my way to save? No. Do I drive spirited? It depends on the situation. Do I drive forward looking? Yes, I see lights that are about to turn red, cars that are about to stop or turn and lift my foot ... activating MDS :)
Last but not least ... it was my "excuse" for not getting the smaller engine and to silence some of my more "greener" friends :) :)
 

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How much gas can you save while coasting? With or without MDS, the coasting MPG is HUGE. The time when a Hemi gulps gas is under throttle, and that is when the MDS isn't active. Just my opinion, and I do not mind the feature (i.e. gimmick) as long as it does not cause other long term problems as a result of the modifications that it took (mechanical and computer).
 

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The MDS system that Chrysler used came from the Daimler side of the house, where it has been in use for years, most notably to bring their 12cyl down to 6cyl. From everything my homework turned up, the system does not cause problems to the engine, and, in fact, does what it promises, although I believe the numbers to be on the high side. You should be able to detect the very subtle transition to 4cyl if you pay enough attention. During my test drive of the Hemi Commander, I was able to feel it by setting cruise control at 60, then throttling up to 70 briefly and then keeping my foot off the gas. It settled back in to 60, then a second or so later there was a minor shift in the engine noise and the average MPG (that I had reset) climbed a bit.

I was not able to detect the shift back to 8cyl, but then, I wasn't expecting to since goosing the Hemi makes for a different type of experience altogether. :)
 

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This is an excellent idea. Even hybrids are getting some negative reviews with inflated numbers. Looks like manufacturers are backing off their inflated claims with these now. The cool thing about the MDS is that it doesn't require an electric motor, huge batteries and other hardware. It's a good start and better than nothing at all.
 

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..And as I posted in another thread yesterday, IT WORKS. I was getting mileage figures in the 24mpg range at 55mph. That's definately as good as a 6cyl, if not a 4.
 
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