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Old 07-23-2018, 11:51 PM   #4 (permalink)
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Join Date: Dec 2014
Location: Butte, Montana
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little jona - '91 Dodge D 250 first gen cummins LE
Team Streamliner
90 day: 23.4 mpg (US)

Little Jona airo modded - '91 Dodge RAM 3/4 TON D 250 24 AUTO
Team Cummins
90 day: 18.5 mpg (US)

The Salted Hound Jenny. - '87 Dodge Ram 50/D-50 5sp 4X4
90 day: 20.24 mpg (US)

Jona Allison aero - '91 Dodge Ram D-250 Le
90 day: 20.76 mpg (US)
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Thanked 425 Times in 276 Posts
Very cool, but about half of it still outside my experience and therefore not fully understood (yet).
The servo refrences the reastat/ potentiometer ( dial adjusted resister) to know what angle the arm is. With out a signal from the raido the servo goes to defalt center x ohms if the reastat is putting out more or less than x ohms it knows to move left or right. We can tell the logic bord that the arm moved by changing the resistance it sees on the yellow wire. When it sees this change it will send the appropriate polarity to the motor to correct the position.
We have hijacked the power to an external motor. This motor moves the control rod conected to the luver. There is a 2nd refrence rod that is connected to the arm. When the refrence rod moves the arm to the correct spot the change of resistance (from the thermister) is compensated for on the reastat. Now the lodgic bord thinks the servo is centered.
Duse this help?
1st gen cummins 91.5 dodge d250 ,HX35W/12/6 QSV
ehxsost manafulld wrap, Aero Tonto
best tank: distance 649gps mi 24.04 mpg 27.011usg
Best mpg : 31.32mpg 100mi 3.193 USG 5/2/20

'83 GMC S-15 Jimmy 2door 2wd O/D auto 3.73R&P
'79 Chevy K20 4X4 350ci 400hp msd custom th400 /np205. 7.5-new 14mpg modded befor modding was a thing
87' Hyundai Excel
83 ranger w/87 2.9 L FI2wd auto 18mpg on the floor
04 Mitsubishi Gallant 2.4L auto 26mpg
06 Subaru Forrester XT(WRX PACKAGE) MT AWD Turbocharged 18 plying dirty best of 26mpg@70mph
95Chevy Blazer 4x4 auto 14-18mpg
04 Chevy Blazer 4x4 auto 16-22mpg

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