Here are the speedo calibration numbers for a stock 4L60e 2002 Camaro SS.
The stock tire is approx 25.7 inches with a circumference of 80.6 inches and turns about 787 revs per mile. With the stock 3.23 axle the calculated transmission revs per mile is 2,542 revs per mile. This compares favorably with the 2,615 that shows up under the calibration tab.
Here is the modified calibration using wizard for 26.4 diameter MT drag radial with a circumference of 83.0 inches and turns about 764 revs per mile. With the 3.70 axle the calculated revs per mile is 2,826 revs per mile. The does not compare favorably with the 3,781 that the wizard calculates.
Even doing a simple compare ratio of 3.70/3.23 applied to the factory 2,615 results in a value of 2,995 which is a long ways off the wizards value of 3,781.
I took the car out on the highway and the speedo, scanner and GPS were all very close at 60 mph.
In the note it states that the output shaft rpm is used to calculate shift rpm and tcc. Could this be why I have no WOT 1-2 and 2-3 shifts even though the mph and rpm targets are exceeded by quite a bit.
What am I failing to understand here?
2002 Camaro SS auto 3.70 26.4 drag radial.jpg2002 Camaro SS auto stock tire.jpg