gas mileage / larger injectors
09-22-2009, 12:43 AM
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gas mileage / larger injectors
here is a bit of info for those who watching their avg mpg. let it be known once you go above 42's. this gauge is no longer of use to you.
simple understanding of where it comes from, and how it is put together in the ecm is harder than it seems. figuring out how it works is easy.
lets say you're a ******* like me and put 98lb injectors in your car. fill up with e-85 that already takes 30% on average more fuel. however, you're "miles till empty" reads 597. odd.
comparing old logs vs the recent ones one can see one major difference. the m/sec idc is a lot lower. cruising down the highway at 2% idc is amusing.
the calculation is done average between m/sec and u/sec {i think. opening time of the injector} put against, speed, and rpm more or less.
how do i know this? because there is no way in hell i am pulling down 47.5 mpg on e85, and spending 20 bucks every two days to fill back up.
simple understanding of where it comes from, and how it is put together in the ecm is harder than it seems. figuring out how it works is easy.
lets say you're a ******* like me and put 98lb injectors in your car. fill up with e-85 that already takes 30% on average more fuel. however, you're "miles till empty" reads 597. odd.
comparing old logs vs the recent ones one can see one major difference. the m/sec idc is a lot lower. cruising down the highway at 2% idc is amusing.
the calculation is done average between m/sec and u/sec {i think. opening time of the injector} put against, speed, and rpm more or less.
how do i know this? because there is no way in hell i am pulling down 47.5 mpg on e85, and spending 20 bucks every two days to fill back up.
09-22-2009, 12:49 AM
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Ya 47.5 mpg doesn't seem even close to right lol. However I am sure your odometer still works. How many miles, roughly, do you get to a full tank of gas on e85 out of curiosity?
Thanks for the information, you have been very helpful to the forums lately, is something wrong? Are you dying? Just kidding man, thanks for the info!
Thanks for the information, you have been very helpful to the forums lately, is something wrong? Are you dying? Just kidding man, thanks for the info!
09-22-2009, 01:01 AM
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Ya 47.5 mpg doesn't seem even close to right lol. However I am sure your odometer still works. How many miles, roughly, do you get to a full tank of gas on e85 out of curiosity?
Thanks for the information, you have been very helpful to the forums lately, is something wrong? Are you dying? Just kidding man, thanks for the info!
Thanks for the information, you have been very helpful to the forums lately, is something wrong? Are you dying? Just kidding man, thanks for the info!
little things here and there that someone might ask in the back of their head like this are always good to have floating around sometimes.
now as far as asking how to tune 98lb injectors? that is going to take more than a post to explain. i am just lucky to have a ******* awesome fuel guy working with me on getting this right.
09-22-2009, 01:03 AM
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Sorry to hear your nerves are fried. I am getting ready to attempt to tune my 80lb injectors, granted there are base maps floating around and more information on them then 98lbers *which have nothing out there* so I am sure it will be much easier, but I have a feeling I might be in the same situation you are. I just really hope I can get my fuel trims dialed in and that my idle is as close to stock as possible.
09-22-2009, 01:04 AM
#9
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I see this mpg inflation with 60's in my 2.4...
http://s337.photobucket.com/albums/n...rent=50mpg.flv
http://s337.photobucket.com/albums/n...rent=50mpg.flv
09-22-2009, 01:07 AM
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No problem. I am curious to see if the people on e85 have clogged fuel filters quicker then 93 octane guys. I hear e85 is extremely dirty fuel.
Haha watching is VERY helpful
Haha watching is VERY helpful
Last edited by Zach06CobaltSC; 09-22-2009 at 01:07 AM. Reason: Automerged Doublepost
09-22-2009, 08:47 AM
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Doing my miles driven divided by gallons filled up, I got 37.6 mpg on my drive from Indianapolis to home. That's with the first 75 miles driving w/ DFCO disabled and doing a few pulls. Even had my dogs and 100# of crap in my car from my weekend trip.
My DIC showed 38mpg. So, for me, it wasn't that much off :shrug:
My DIC showed 38mpg. So, for me, it wasn't that much off :shrug:
09-22-2009, 08:49 AM
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09-22-2009, 09:49 AM
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Sorry man that sucks....hell if 47.5 mpg was right with 98lb injectors I think we would all be doing that lol haha, go back to pump and save yourself money at the pump..
09-22-2009, 04:43 PM
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I don't really see the advantage of switching to E85 over running 93/Water/Methanol, the gas mileage is worse with it and the octane rating is the same, then your also limited in places you can get it. Seems like a lose/lose situation to me.
09-22-2009, 05:16 PM
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e85 is around 105 octane.
09-22-2009, 06:44 PM
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