[jagarner70]

I just switched over to a Auto meter sport comp tach and I am having trouble. The rpms are reading 500-700 high. The techs at autometer had me check the voltage at the tach and it was 13.8. I would like to avoid sending the tach in for inspection and I thought Id ask here if anyone has a suggestion? I have a MSD Blaster coil, MSD Streetfighter plug wires and a dual point Mallory dist converted over to petronix.

 

[AzPete]

Is there a switch for 6 and 8 cyl engines? If so, ensure it is proper and even switch it back and forth a couple of times to ensure proper settings.

 

[Big_B]

Do you have another coil laying around? I had something similar happen with a vintage tach and when I switched coils it started working. I think it had something to do with the resistance of the old (accel super stock) and the new (pertronix) coil.