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How to tune for best gas MPG

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Old 05-21-2008, 03:20 PM
  #46  
Rogue_Ant
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Originally Posted by nize
i wasn't patronizing, i was pointing out an obvious fact. assuming you're driving consistently with the same start and end speeds, accelerating downhill and shedding speed going uphill (with the gas down the whole time) vs. coasting downhill (with no gas) and maintaining speed uphill (using more gas) would net an equal amount of gas consumption. this is basic physics.
If it is an obvious fact, then it doesn't need to be pointed out (obviously). That you did point it out regardless is being patronizing.

Perhaps I'll refine my wording, slightly. Mild acceleration downhill and minimal throttle uphill.

If you close the throttle down-hill, then the dynamic braking of the engine is counter-productive. So you are not using the downhill to your advantage, and then fighting your way uphill.


-Rogue
Old 05-21-2008, 09:10 PM
  #47  
marky522
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The E-85 talk is very interesting, What is required beyond the tuning ability and wideband? I was thinking of going MS anyway this may be a good reason.

Mark
Old 05-21-2008, 11:01 PM
  #48  
951_for_John
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I have interest in E85 as well, although as of now it is unavailable in my area.

Rogue, is higher boost the key to your MPG, as most flex fuel vehicles have less MPG on E85.

John
Old 05-22-2008, 01:53 AM
  #49  
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Originally Posted by marky522
The E-85 talk is very interesting, What is required beyond the tuning ability and wideband? I was thinking of going MS anyway this may be a good reason.

Mark
I suggest replacing the rubber lines in your fuel system as a precaution. Since E85 takes roughly 25% more fuel for the same air mass, your fuel system needs to be able to flow enough for the more fuel.


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Old 05-22-2008, 01:58 AM
  #50  
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Originally Posted by 951_for_John
I have interest in E85 as well, although as of now it is unavailable in my area.

Rogue, is higher boost the key to your MPG, as most flex fuel vehicles have less MPG on E85.

John
John,
Using E85 will always return a lower MPG then Gasoline. My MPG numbers was on premium Gas. I really haven't tried for the best mileage possible on E85, simply because I can't keep my foot out of it.
To return the best MPG, you want to stay out of boost as much as possible.

The reason I run E85 is that it allows for very high boost levels without knock, and can be bought at the pump for significantly less then premium gas.


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Old 05-22-2008, 02:24 AM
  #51  
zoltan944
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Yes, you will not get better MPG on E85. Im running E85 to try to come out cheaper per tank. Run a little more advanced. Support an alternative source of fuel. Id like to see more stations get it and more solutions funded.
I take 700 mile round trip runs 3 times a month. I try to stay off as much boost as possible on the drives. E85 can run pretty lean cruising. I am going to get an average of what kind of MPG I can get out of this stuff. Some others have proven the power levels E85 produces. Im gonna see what kind of economy it can render when needed.
Old 05-22-2008, 02:43 AM
  #52  
blown 944
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as much as I love E85 I would never suggest it for best mileage over gas.

However after running it so long I just took a road trip in my little mini van and I can say that I truly hate the smell of regular gas (had to use it on the way out). Fortunately for me I found 2 stations along I 70 in KAnsas that had E85 so all is good
Old 05-22-2008, 04:08 AM
  #53  
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so who is going to make a e-85 kit for the 951's????
Old 05-22-2008, 05:49 AM
  #54  
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...you might be able to cut a deal with blown944. He can source all of the parts from the Pick'n'Pull. If you're lucky, he might even throw in the rust for free
Old 05-22-2008, 06:55 AM
  #55  
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Originally Posted by turbo8
so who is going to make a e-85 kit for the 951's????
There is a Swedish Rennlister who has put together a MAF kit with both gas and E-85 maps on the chip.



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