Real Time Engineering Tach Board Adjustment

[Charger Fan]

Has anyone got experience with putting one of these Tach boards in to replace the factory board. I had one recently installed in the factory tach on my ‘73 Charger. I’m trying to get the idle RPM shown on the Tach up about 200-250 RPM to match what the engine RPM is. There is a 4K screw and a 1K screw on the back of the board for adjustment. Holes were drilled in the back of the case to enable adjustment of either screw with the tach installed. The instructions provided and also on the Real Time Engineering website aren’t exactly the best. The instructions appear to tell you to adjust the 1K screw to increase idle speed. Okay great, but which direction do you turn, clockwise or counterclockwise, and how much/how many turns should be expected to increase RPMs by the 200-250? Do you need to adjust both screws to get the increase? I’ve emailed Greg at Real Time but haven’t heard back. Any help or insight would be greatly appreciated.

 

[kiwigtx]

No experience here, but common sense tells me that you would only adjust by small increments - like a quarter turn at a time and let the needle settle each time you make an adjustment.

Also, you need a verified engine speed from another tachometer before making adjustments....otherwise you're just shooting blind.

 

[Charger Fan]

I have a reference tach hooked up to use in the calibration process.

 

[Paul_G]

Is 250 rpm within the margin of error? How do you know the RTE is off?

 

[69Bee]

You put the shorting plug (red or yellow depending on what is supplied) on pins 2&4, then adjust the Blue variable resistor either CW or CCW to get the needle to read 4000 RPM. Then you move the shorting plug to pins 1&3 and adjust the cardboard piece (which is connected to the needle clock spring to obtain a reading of 1000 RPM (basically zeroing the needle) (pic 12). Then move the shorting plug to pins 3&4 for normal operation and finish assembling the tach.

www.rt-eng.com/images/c/ce/M5tachboard_manual.pdf

 

[pnora]

Holes were drilled in the back of the case to enable adjustment of either screw with the tach installed.

Thats not following the instructions.