Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Re-geared and free-spinned the 3500 4x4 diesel

skyking · 12-20-2016, 09:03 PM

With the new gears it was ~60 MPH at ~1750 RPM.
The OD ratio went from 0.79 to 0.74
This is a change of roughly 6.25%
This brings it down to ~1640 RPM
I use the ~ because the tachometers on these things are not precision instruments

So now I am below the peak torque of the standard cam.
I have a call in to the cam manufacturer to see what they say about peak torque.

12-20-2016, 09:03 PM	#28 (permalink)
skyking Master EcoModder Join Date: Apr 2011 Location: Tacoma WA Posts: 1,399 Woody - '96 Dodge Ram 2500 SLT Team Cummins 90 day: 23.82 mpg (US) Avion and Woody - '96 Dodge/Avion Ram 2500/5th wheel combo 90 day: 15.1 mpg (US) TD eye eye eye - '03 Volkswagen Beetle GLS 90 day: 49.05 mpg (US) Mule - '07 Dodge Ram 3500 ST Thanks: 743 Thanked 528 Times in 344 Posts	With the new gears it was ~60 MPH at ~1750 RPM. The OD ratio went from 0.79 to 0.74 This is a change of roughly 6.25% This brings it down to ~1640 RPM I use the ~ because the tachometers on these things are not precision instruments So now I am below the peak torque of the standard cam. I have a call in to the cam manufacturer to see what they say about peak torque. __________________ 2007 Dodge Ram 3500 SRW 4x4 with 6MT 2003 TDI Beetle 2002 TDI Beetle currently parked - 1996 Dodge 2500 Cummins Turbodiesel Custom cab, auto, 3.55 gears