Porsche 924 rev counter help

[blitzvw]

Hi guys, I have a Porsche 924 rev counter that I would like to wire into a Beetle/Type 3

The one that I have is from a '77 924 and has 3 terminals at the back.

One that says +12
One that says 1
One that says - (minus)

What goes where? Can anyone help?

Thanks

[evilC]

A guess?

+12 is to the +ve on the ignition switch circuit
- is earth
1 Is the feed from the coil

???????

Does the unit have a separate circuit for the internal lamp?

Clive

[blitzvw]

Yes, it has two plug on connectors for the lights. I guess that you could pull current for those lights from the speedo lights.

Can anyone confirm that it is indeed the correct way of wiring up?

[NO_H2O]

That is how I would wire it.
12 to key on power +
- to gnd
1 to neg side of coil or tach out of CDI box
daisy chain the lights to the speedo lights so they will be on the dimmer with the speedo.

[blitzvw]

Good stuff, thanks :)