NOTE: My vehicle speed is monitored by a stand-alone GPS speedometer; not a PCM controlled indicator. That stated...
When entering my actual tire size & gear ratio (37.7" / 4.56:1) in the Gear/Tire Calculator, the MPV1 VCM Editor mis-calculates my VSS pulse per mile. it reads as follows under the General tab:
VSS Pulses per mile: 97.574
Final Drive Ratio (4.56) Transmission Revolutions/Mile: 2,592.5972
My Manual Mathematical Calculations:
There are 63,360 inches in a mile.
My 37.7" Tire will hypothetically travel 118.378 inches per each rotation; 37.7 * 3.14 = 118.378
If 118.378 inches is equal to 40 VSS pulses, then:
There are 535.234587507814 VSS pulses per mile; not 97.574
I humbly realize my tuner is antiquated, but it is all I have. How do I correct / align the incorrect VCM Editor Speedometer General Tab entry values generated by the Gear/Tire Calculator? They are clearly way off and my 4L60E shift scheduling is less than optimal. I figure these basic entries here may have something to do with my shift timing dis-satisfaction.