Tacho wiring

[OLFOOL]

I'm trying to get the tacho working, I can only find wiring diagrams using either an MSD box or ready to run MSD distributor with 4 wires mine only has the 2 and using a Bosch BIM024, I believe I need to use the MSD Tach Adapter 8920 to run the analog tacho. Any help with a wiring diagram appreciated

 

[Dana67Dart]

How many wires does your analog tach have?

Older style tachs got their signal from the negative side of the coil. (Point and OEM Chrysler electronic ignition) Not sure what modern techs use.

Iirc the msd adapter was to eliminate the "multiple" spark the MSD produced and give the tach a single signal to fire.

 

[OLFOOL]

How many wires does your analog tach have?

Older style tachs got their signal from the negative side of the coil. (Point and OEM Chrysler electronic ignition) Not sure what modern techs use.

Iirc the msd adapter was to eliminate the "multiple" spark the MSD produced and give the tach a single signal to fire.

yes it's a single dark green wire to the tacho from the negative side of the coil. It is electronic ignition using a Bosch BIM024 ignition module instad of the factory box, ballast resister etc. I'm using Msd 8534 and a Blaster 2 coil.

 

[67Dart273]

That info should be available right on the MSD website

 

[OLFOOL]

That info should be available right on the MSD website

Nope, doesn't show any information or diagrams that I need, always with an MSD box which I am not using.

 

[67Dart273]

Nope, doesn't show any information or diagrams that I need, always with an MSD box which I am not using.

Of course it is. Download this

https://documents.holley.com/techlibrary_9615_wdtn_2014.pdf

May not be all but check pages 196 +/-, and 164 and greater,

 

[OLFOOL]

Of course it is. Download this

http://[URL]https://documents.holley.com/techlibrary_9615_wdtn_2014.pdf

[/URL]

May not be all but check pages 196 +/-, and 164 and greater,

Mate, please show me what wiring diagram you are suggesting as all I see are the ones which all have MSD boxes and not 4 wire ignition GM style modules like the one I am using for the tach adapter?

 

[67Dart273]

For some reason I thought you WERE running an MSD. In your case you should only need to add the tach to the coil NEG terminal

 

[OLFOOL]

For some reason I thought you WERE running an MSD. In your case you should only need to add the tach to the coil NEG terminal

I am running an MSD dizzy, but a 2 wire one, and the standard green wire to the - side of the coil does not work as the dizzy is digital and the Valiant tacho is analog.

 

[67Dart273]

I am running an MSD dizzy, but a 2 wire one, and the standard green wire to the - side of the coil does not work as the dizzy is digital and the Valiant tacho is analog.

So what is this thing? This distributor? Part no.? model no?

The Bosch module is nothing more than a different type of module similar to a GM HEI module. There is NOTHING digital about it

 

[OLFOOL]

So what is this thing? This distributor? Part no.? model no?

The Bosch module is nothing more than a different type of module similar to a GM HEI module. There is NOTHING digital about it

View attachment 1716313690

I explained the parts/numbers in my 2nd message, I know the module is not digital but the signal from the distributor I believe is digital, diffrent to analog.

 

[67Dart273]

I explained the parts/numbers in my 2nd message, I know the module is not digital but the signal from the distributor I believe is digital, diffrent to analog.

There is nothing "digital." Heed what I told you. The module you have is nothing different than an GM HEI or a Mopar factory 4 wire ignition box. The MSD dist is nothing more than a magnetic pickup just like a GM HEI or a Mopar factory breakerless. HOOK THE GREEN TACH WIRE TO THE COIL NEGATIVE POST
Bye