by thrashingcows » Thu Nov 06, 2014 1:35 pm
I was digging through old threads over on Cumminsforums, when i came across a board member "Left out in the cold" who had been advising people on how to figure out what ratio adapter they needed.
Here is a quote from this helpful board member....
2wds are different than the 4wds. The 4wds have a ratio adapter between the transfer case and the vss. You need to find the % error. The way to do that is to remove the adapter you have and install the vss directly to the transfer case. Pace someone who is going 50mph and note what your speedo says. How much it is off will be 50% of your total error. All you need to do now is find an adapter with that % correction.
I did this with a friends GPS unit to figure out my error. I was reading 67Kph when actually doing 80kph. So you then divide the speedo reading into the actual speed you were traveling and I came up with 1.194...so a +20% was needed.
1984/93 Dodge Crewcab, W350, 1 Ton SRW, long box, 330K Km's, M&H spacer, 366 spring, fuel pin to deep side, 14cm housing, Piston LP, PS IC, Isspro Boost, Pyro and tach, NV4500, 29 spline NP205, 3.54's.
Check out the build....
http://www.dieseltruckresource.com/dev/ ... 05923.html