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Old 07-27-2017, 01:40 PM   #45 (permalink)
gumby79
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Join Date: Dec 2014
Location: Butte, Montana
Posts: 725

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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Dose the bow wake from the semis push you sideways or caus a rotation around the center of pressure?
Had a Hyundai Excel that would squirt sideways, (not rotation) just behind the rear bumper of a truck I would get sucked over tord the trucks wake. The trailer/ cab gap only had effect on heavy wind days (30+) As my front bumper would entre the bow wake tbe front got pushed(CP artificially forward) , at my door the force was square (balanced CP) at my rear bumper it would push the back out rotating my trajectory into the trucks path (witbout correction.) (Artificialy biassed ththe rear
Point is;
If its rotating a rudder, fixed or dynamic, balince the CP.
If its squirting sideways , then downforce would be the fix,

Unscientific methodology for testing center of pressure in Dynamic wind.
Place on blocks of ice in cross wind and mesure the side force applied to each wheel center .
clading the spokes
This was popular with bike raicers in the 90's but favor quickly went for profiled spokes over disk,less gain but still a gain in more wind conditions. The disk is better for always in ahead wind ,but roads never seem to cooperate. . If you find your CP off oneway or the other use the disk on the light end this may be what your looking for.
To get more out of the front a-arms without a rebuild/skin . Add a gurney flap.
__________________
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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