1969 C6 SCJ output shaft speedometer drive gear

[KR500]

I am working on a 69 Mach1 SCJ C6 car ( W code 4.30:1 ). Car has inaccurate speedometer and bouncing indicator needle. The car has been converted to a 3.50:1 gear, and not using the gear reducer. I got the correct driven gear for the 3.50's and tire size. Same problem. I pulled the cable and gear out and using my finger I was able to spin the drive gear easily. Is something different with a SCJ C6 output shaft? I though all C6's had the drive gear machined on the output shaft? I did not see anything listed different in the MPC. It acts like a toploader with a broken dive gear retainer. Any thoughts?

Thanks
Rodney

[Corey Bowcutt]

Rodney,

I can not really address much of your question because I have no experience with big blocks or auto transmissions but I thought I would just share my experience with a bouncing speedometer.  I had that in my 68 GT350.  I tried lubricating the cable to no avail.  So I ultimately just bought a new speedometer cable and the problem went away.

I think I also remember that manual and auto transmissions have gears that spin in opposite directions but again I am out of my league here.

Corey