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Old 07-28-2017, 06:12 PM   #7 (permalink)
gumby79
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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 2×4 AUTO
Pickups
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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Take the weight on a single tire divide it by the psi = the size of the contact patch . Eg my dodge 2500lbs rear axle ÷2 =1250÷side wall max+20%96psi =13.02^" Vs proper air for flat even wear@60psi =20.8^" which one will work better under anything other than straight line?
The performance gained in cornering from raised psi is the over inflated tire being convex compensating for the lack of camber and less slip angle (the difference between how much the wheel turns Vs how much the tred turns)
Eg. the tred is pushed sideways in a hard corner,
Over inflated stock camber, when it will run on the center and sholder.
Data plate/stock camber , sholder and side wall and some center.
Low air will fold under running on the sholder and sidewall when low enough the rim makes contact normally resulting in a flip.
Proper air with proper camber, will run flat.shoulder to shoulder

If you want the ultimate advice get a $20 Infered temp gun. The air is proper when the tire reads the same +-2°f across the tread. As in the formula above this psi # is in a constant state of flux.as you change what or how many things in the car and burn gas so will the weight distribution and volume . Go for 1/2 tank and normal load to get your psi/temperature

One more thing to consider is excessive shock loading/jarring causing abnormal suspension part wear= higher maintenance cost and slower cornering speed (slopy steering add RR )
__________________
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


Former
'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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