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MPG fooler - Design phase

Mopar1973Man
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Heavyd1980

Heavyd1980

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wow this is huge now! hard to keep up but doing my best to cant wait to see what comes next:shrug:

--- Update to the previous post...

I'd pass a stone the size of Kansas, if my 24v would break >19mpg on the highway.. Hell, I'd like to see > 14 in town.

My 12V with #10 and 38psi boost got 17-18 in town, and 26 on the highway at 68mph (CC) from VA to NY.

I've used 3/8 tank on this last fuel up, and I've barely reached 120mi.

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SASQCH

SASQCH

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I see about 13mpg in town with my 24v and so far the best ive gotten out of about 25 gallons is 330 miles!!! which my best guess is about 16mpg thats un-corrected of course since im running 315 tires:doh:

Do the math 330 / 25 = 13.2 If your truck is a 98.5 dually the 315/85 16 tires are the stock size. Not sure what the SRW size should be.
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Heavyd1980

Heavyd1980

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Do the math 330 / 25 = 13.2 If your truck is a 98.5 dually the 315/85 16 tires are the stock size. Not sure what the SRW size should be.

right what i meant by that was the correct mileage since 315/75-16 are what im running and 245/75-16 is the stock size that came on my truck!!!
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Rogan

Rogan

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Do the math 330 / 25 = 13.2 If your truck is a 98.5 dually the 315/85 16 tires are the stock size. Not sure what the SRW size should be.

WTF? :nono: was that a typo?

right what i meant by that was the correct mileage since 315/75-16 are what im running and 245/75-16 is the stock size that came on my truck!!!

Thats more like it, size-wise... 315/85/16 is almost a 37x12.50
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SASQCH

SASQCH

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Are you sure??? 235/85 R16 and 265/75 R16 are both 31 inch tires... Just about 1.5" difference... I know the 245/75 R16 was used as well...

Yes Mike, I'm sure that the 98.5 DRW (two tires on each end of the rear axle) truck is 215/85/16 from the factory unless the sticker on the door frame and the stamp molded into the tires both are a typo from the factory. I run stock size 215/85/16 in the winter with studs and go to 235/85/16 for summer. Jim
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SASQCH

SASQCH

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The sticker is the factory recommended size, that don't mean that a larger size won't fit or work well. The speedometer is almost always calibrated to the tire size on the door sticker so if a larger size is put on, there should be a recalibration of the speedometer. As you probably already know the easiest way to check the accuracy of the speedometer calibration to actual is with a GPS. On my truck I have a box from superlift that corrects for tire size and can be micro adjusted for absolute accuracy. It has a toggle for two tire size settings. I have it set for 215 and 235 respectively so when I switch tires (they are all on rims so no mount/dismount required) all I have to do is flip the toggle and the speedometer is re-calibrated.Just as a matter of interest Sam's club tire shop (at least here in Alaska) will not mount any tires of a different size than listed on the factory door sticker.Jim

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Heavyd1980

Heavyd1980

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The sticker is the factory recommended size, that don't mean that a larger size won't fit or work well. The speedometer is almost always calibrated to the tire size on the door sticker so if a larger size is put on, there should be a recalibration of the speedometer. As you probably already know the easiest way to check the accuracy of the speedometer calibration to actual is with a GPS. On my truck I have a box from superlift that corrects for tire size and can be micro adjusted for absolute accuracy. It has a toggle for two tire size settings. I have it set for 215 and 235 respectively so when I switch tires (they are all on rims so no mount/dismount required) all I have to do is flip the toggle and the speedometer is re-calibrated. Just as a matter of interest Sam's club tire shop (at least here in Alaska) will not mount any tires of a different size than listed on the factory door sticker. Jim

What is the install like on that superlift box, and wow ive never heard of a tire shop not wanting to install tires no matter what the dor sticker says??:stuned:
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SASQCH

SASQCH

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What is the install like on that superlift box, and wow ive never heard of a tire shop not wanting to install tires no matter what the dor sticker says??:stuned:

Install was quite simple as I remember it, it splices into the speed signal wires from the transmission and the box mounts in the cab. I got it around 2002 from jc whitney. Ive been quite happy with it. The hardest part (and that isn't hard) is calibrating it to your tires using a GPS and a straight level highway that you can set the truck on cruse control and using a small screw driver adjust the screws until the GPS and speedometer or SG II (if you have one) read the same speed. The tire shop cited liability reasons for not mounting oversize tires, wall mart and Sams got scared by the firestone blowouts a few years back I think. Here is a link to the unit at superlift: http://www.superlift.com/accessories/truspeed.asp Jim
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Heavyd1980

Heavyd1980

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Install was quite simple as I remember it, it splices into the speed signal wires from the transmission and the box mounts in the cab. I got it around 2002 from jc whitney. Ive been quite happy with it. The hardest part (and that isn't hard) is calibrating it to your tires using a GPS and a straight level highway that you can set the truck on cruse control and using a small screw driver adjust the screws until the GPS and speedometer or SG II (if you have one) read the same speed. The tire shop cited liability reasons for not mounting oversize tires, wall mart and Sams got scared by the firestone blowouts a few years back I think. Here is a link to the unit at superlift: http://www.superlift.com/accessories/truspeed.asp Jim

Sweet thank you Jim I will have to look into one of these!:drool:
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flagmanruss

flagmanruss

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The local discount chain sales clod argued with me... He'd looked in his book & it said my POS econo box (my previous DD) took 15" tires. I had to show him the OEM wheels were 14". Duhh!! They would only sell you tires listed as available on that vehicle. Come to think of it, they even gave me a hard time about putting Cooper Discoverer M&S Truck tires on my Ranger PU (early 80s, 2.2 natural). Actually they were on sale & I had the closest store call around, I got the 4 tires from 3 different stores! When the Ranger tranny gave up the Ghost, I had them remounted on wifee's Carovan where they wore like iron! (Same exact size, just Truck tire).

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ISX

ISX

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No kidding ..... I have my juice off (sold it) and am going to a QUAD. Its very DOG DOG slow and MPG is down 2-3. Will get QUAD sometime his week. Not expecting any difference - but will keep posted. Mike/ISX - assume this IAT fooling really only works for winter though right ? In summer the timing will be advanced as far as possible due to the voltage of the IAT mappings ?? :shrug:

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Mopar1973Man

Mopar1973Man

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Ok... Run #2

I change thing on the truck a bit to match ISX as much as possible.

[*]Change my Cooper STT's 265/75 R16 to my Big O AT's 235/85 R16

[*]Removed the winter fronts

[*]Turned ON the Edge Comp 5x5

The same resistor was used again. 2.7K ohm (132*F IAT temps)

Now I ran the trip again to New Meadows, ID the roads are snow covered, current weather is 3*F above, light to no winds, speed ranging between 45-55 MPH with some use of 4WD. When I reached New Meadows I had a few stops to make so during the stops I used the 6 cylinder high idle. When I got to my final stop I shut down for about 2 hours. (Stopped a friends house) Then fired back up and left for home. Pulled in the driveway with 19.5 MPG on the SGII...

I'd say that a winner in my book... :hyper:

PREVIOUS TEST WITHOUT EDGE COMP

Test run done... (You don't want ot hear it...)

Edge Comp turned OFF!

Round trip to New Meadows, ID and back home (40 miles) pulled 12.5 MPG! :sofa:

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ISX

ISX

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It had more power without the front too, didn't it. It hit 67F here (pretty sure we broke a record) and I had to step on it and it was back to being a little slower. When it gets under 20F I can just fly, spools like crazy and everything. Time to add another toggle to the high idle box :lol:

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