DMCNick

So how did this turn out? I want to use the same speedometer behind another gauge face but I need a way to calibrate the sensor. Did you ever get the other circuit made? If so I'd LOVE to see the circuit. And why is the second circuit (LM2907) needed? Cannot the VSS be read as a dc signal as well as a pulse. I recall that Ford tests the VSS with a DC meter. But I could be wrong. More recent reading indicates it is AC. Check out this link... http://v8nissans.com/forums/content.php?113-S14-speedometer-correction-with-z32-tranny-the-free-way It implies that a variable resistor across the indicated resister pads (resistor removed) could be used to tune the speedo to any drivetrain. Once the resistance is determined a trim resistor or fixed resistor could be soldered in-place. Inquiring minds want know ... Nick