Hi, I've got a 1972 Cutlass supreme without any stock rpm gauge. I'm looking into installing an rpm tachometer, but I've got a few questions. Most importantly, where does the wire attach to get the rpm readout? I've heard some people suggest the distributor, but not specifically on which part of the distributor. I was wondering if anyone knew how to, or had a guide or video on how to wire it. Thanks for any help!

 

On a car with points ignition, the sensor wire connects to the (-) terminal of the coil.

On a car with HEI, the sensor wire connects to the TACH terminal.

Other ignition systems have other requirements.


The instructions that come with the tachometer will tell you.

These, for instance, which I found just now, using Google:
http://www.carid.com/images/sunpro/c...structions.pdf



- Eric

 

I just did a Sun Tach install on my 70.
Red - to the fuse tab labeled "BATT" (they give you a connector to solder on)
Black - Ground to body
Green - to the NEG tab on the coil
White (optional) - to the dimmer switch for the lights, or the fuse panel

 

FYI, the TACH terminal on an HEI distributor produces the same signal as you would see at the - terminal on a traditional coil As noted, nearly every aftermarket tach has a sense wire that connects to the - side of the coil.

 

Diesel tachs connect to the alternator.

 

Wiseguy.

- Eric

 

Lol, just sayin....

 

And the ones I have seen don't go to 6000 RPM.