I have a 700R4 and am using a speed sensor from a 92 Z-28 which has the VSS and cable drive. I have a 17 tooth drive gear, 27 inch rear tires and a 3.08 rear. Can someone tell me if I'm correct in thinking I need a 40 tooth driven gear? Actually the math says 30.07 driven, but the VSS handles 40 thru 45 teeth. Am I correct in my thinking? I just don't want to be in the tranny more than once. Thanks

 

I'm buying the gear tomorrow and I will let everyone know when I get it back together.

 

What you need to do is figure out the percent the speed is off. The drive gear would be the one on the trans output shaft. The Speedo gear would be the driven gear. If driving at 70 MPH and your speedo is reading 77 MPH, you have 10% fewer teeth. with 17 teeth on the driven gear you would need 1.7 more teeth to slow the gauge down. If you are doing 70 MPH and your speedo is reading 63 MPH you would need 1.7 teeth less to speed up the gauge. Your gauge will not be off 5 MPH or 10 or 15 through the entire sweep. It will be off in %, the faster you go the more it will read fast or slow.
If that helps.

 

1991L98G92, thanks for the reply. As it is right now, I have a regular sleeve and and I know the drive gear is red 17. I couldn't remember the driven gear number, so I was trying to avoid doing this twice. The speedo is dead on right now, but I'm getting ready to pull the regular sleeve and install a VSS with cable drive as well. The ECM has convinced me it needs the VSS signal to decellerate properly. With all that, it is my understanding, with the known parts of this puzzle, I need the black driven gear. (I hope).