Recently I have been working with a T42 and a 4L60E. When I run it on a dyno I get really high speed output numbers. 240Kmph. actual speed around 60mph. I went into the speedo calculator function of the programming and and the pulses per km are way big. toward the upper limits of efi live. When I change the tire size and gear an try to apply changes it wants to change 24856% ? so I apply it and it doesn't really do anything. My question is why is the number so high in the first place? The older LS1 speedo calculator has realistic numbers but not the T42. I have 1 T42 that has a 6 inch diamiter tire programmed into it from the factory? Is GM using a different format for calculations? I would expect to see numbers like 88000 to 133000 PPM but it not even close. Any ideas? I have a 40PPR speed sensor reluctor.