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Positive ground tach/dwell meter hook up

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livinginthepast

livinginthepast

Jedi Trainee
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I just realized that my BE is the first positive ground car that I've owned! So I'm a little confused as to how I should hook up my tach/dwell meter. Do I simply reverse the wiring - ie. black lead to distributor post of coil and red lead to ground? Or will I cook my meter? :smile:

Thx!
 
It sounds like you've got a two lead meter. I'm used to three leaded equipment which would require the "red" lead to go to the chassis of a positive ground car, the black lead could go to the ignition switch side of the coil or to the "hot" terminal on the starter solenoid. The sense lead of the three leaded equipment would go to the "low" side of the coil where the distributor connects.

I assume your summary is correct that for a two lead device you would simply reverse the leads from what they would normally be (red to chassis, black to the dizzy side of the coil).

From memory, if the meter was designed for negative ground... I think my three leaded equipment reads the "inverse" of the dwell. That is to say... if the dwell was supposed to be 60 degrees, I think the meter displayed 30 degrees when used on positive ground. Hopefully others will be able to confirm this for you. Of course, the two leaded dwell meters may behave differently to start with.
 
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