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Discussion Starter #1 (Edited)
all right guys i am trying to figure out my best mpg, and i'm about ready to give up and say there is no hope no matter what speed and no matter what i do i will get 12.5mpg is it better to have more boost or less? i have an aftermarket turbo, but no idea what it is, there are no markings on it except like 5 or 6 numbers that no one can tell me what they mean. can u guys compair the readouts to what u all get to see if i'm in the ballpark with boost vs rpms and so on. i've got 37's so my dash is less than my gps, so gave both. thanks!

RPMS.....GPS.....DASH.....BOOST
1600......56........50..........2psi
1725......61........54..........2psi
1925......68........60..........6psi
2075......72........64..........8psi
2225......78........70..........12psi

bowz
 

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Provided that you're turbocharger is functional, boost pressure is a measure of how hard the engine's working. You get best mileage if you keep your boost pressure low.
 

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Are you hand calculating the numbers? If so are you taking into consideration that the odo is about 11% off due to the larger tires? Traveling more miles than indicated.

MikeyB
 

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I've heard to keep it under 10 lb boost and under 2000 rpm to get best mpg.

But like said, those tires are throwing your numbers off unless you are taking that into consideration.

Lifted doesn't help either. But the looks are well worth it some times...
 

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Are you hand calculating the numbers? If so are you taking into consideration that the odo is about 11% off due to the larger tires? Traveling more miles than indicated.

MikeyB
I agree:thumbsup If you figure out what to multiply your trip meter by to get your correct milage I bet you will find your getting quit a bit better than you think. My truck I have to multiply the trip meter by 1.13 to get my acule milage.
 

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Discussion Starter #6
i figure up my milage with my gps odometer, i average about 110 miles per every 100 miles on the dash. i was just currious on what the boost readings were on a stock turbo, i think mine are verry low for crusing speed, granted once i hit the skinny pedle at 1700rpms it take about 3 seconds for my attitute to peg 39psi, and who knows how high it actually goes. :lol3: or untill :$: for a new head gasket. thanks guys!

bowz
 

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If I understand you question correctly, my 05 does 6psi, 600* EGT, at 60 mph. No load on flat ground.

Hope this helps.

Paul
 

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Discussion Starter #8
yes, thanks just what i'm looking for, any others?

bowz
 

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I think some of your poor mpg is from DRW, 6 in lift, 37/12.5 tires, 4.10 gears and a silencer ring missing so you can hear the turbo sing.
 

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MIA silencer ring shouldn't be affecting mileage, should it????
 

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Silancer ring shouldnt afect your milage un less your driving harder to hear the turbo. I think its the 4.10s more than anything.
 

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I know from a diesel head around here that MIA ring does not adversly effect mileage.
 

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Discussion Starter #13
DBLR, correct you are. i just wish i coudl squezz 16 outa her for this 6k mile trip. also my pyro is about 750 at 62mph with a boost of 2-3psi. a little bit higher than pauls. but even pulling my 3k boat i have only been able to get her to 1200 goin up bridges and what not. besides that empty i got it to hit 1050, and that seems pretty low with all these guys talking about peggen 1500 easily.

bowz
 

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The major difference in EGT's is the thermocouple probe location. You can get a general idea as compaired to others... but unless the TC is in the same spot it won't be too exact.

Also with your Edge it has built in over temp protection that backs down the fueling. If its set for 1200.... you're only going to hit 1200
 

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Discussion Starter #15
ya i gues i never thought about the thermocouple location before, mines right in front of #3. theres no way it could be dirty or faulty right? how can you tell if they go out?

yes my temp protection is set for 1375, i think its 25 above factory preset. it wouldn't start defueling at 1100-1200 with it set at 1375, the egt's don't clim rappidly once it gets to about 975, so mabe it starts defueling there. idk, i guess i'll have to reset my backdown % and see how much it goes up when i get on it pulling the boat. then i'll have an idea. now that i'm thinking about it, there might even be a option to monitor it, never realy bothers cause i never got close... thanks again guys

bowz
 

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No but some people like to hear it whine which in return you have to get in it to hear it
 
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