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Old 01-09-2020, 02:26 PM   #31 (permalink)
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Join Date: Dec 2014
Location: Butte, Montana
Posts: 714

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: 20.84 mpg (US)
Thanks: 206
Thanked 416 Times in 269 Posts
Well done I see more progress.
The rotating mass reductions you have pursued add up to ~60#, I'd venture to guess equates to ~500-1000# of static weight reduction
The 04.5-07 pistons have some special design for emissions
Non EGR CR Cummins duse not exist.
I found this out when researching parts for an 05 medium duty Cummins with a misbehaving EGR valve the wealth of information that is the internet could only tell me I was not seeing what was in front of me and EGR hit the Dodge/light duity in 04 the physical valve didn't show up until the 08.
Re cam the motor is the only way to remove the non cooled exhaust gas non-recirculating system. By closeing the exhaust valve early they were able to trap spent hot exhaust in the cylinder displaces fresh air on intake stroke making a valveless EGR
, I can pull 6th @35 mph running ~900 rpms. never a complaint unless the hill is too steep
How is the 64mm(?s364?) Spooling ,at the extreem low rpms?on grades(5-9%) my 91 with an hx35w12 with a Quick Spool Valve sends in a written complaint using smoke signals running less than 1263 RPM( 55mph in 6th 2ndOD.61, 3.55rear 31.7"tire) due to insufficient air to make power from the fuel causing a rich condition and overly high egts for throttle position and speed 850-1050 ,by 1050@10psi is turning black, drop to 5th(.71 1470 ) 650-750. Or run 66mph (6th.61 1516)and she spools 15-20psi depending on the grade.
IAT 70 ,that would be a wet dream -2to 20 above ambient with the itty bitty baby intercooler the first gen came with.worst seen so far this winter (its been mild) 11 air filter, 120 post compressor, 9f IAT @70mph crossing the ID/MT Continental Divide pass

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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