Can I use 50yr old Handheld Tachometer ??

I

IndyA

Member
I have an old Tachometer (actually also measured dwell & point resistance) that I used on a Negative ground, V-8 auto...has two alligator clips; one red the other black and has analog scale for 6 cylinder & 8 cylinder readings. Can I use this on my '29 A and divide the 8 cylinder reading by 2? ... If "Yes" can one of you experts tell me how to hook it up??? Many thanks for your help.... IndyA
 
Yes! I do it all the time!

If your Model A is still positive ground, connect the red clip to ground and the black clip to the wire coming off of the coil that eventually makes it's way down to the points. On stock Model A wiring, that's the red lead off of the coil.

That's it! Double 8-cyl. engine readings for a 4 cyl. engine. That is, if the 8-cyl. scale reads 200 RPM, that is really 400 RPM on a 4-cyl. engine.

:D
 
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On my old 6/8 cylinder dwell/tach meter it says to multiply (not divide) the 8 cylinder reading by 2 to get the 4 cylinder reading.
Which is correct?
 
Yes, of course, double for 4 cyl. I can never remember doing it from memory by I know what to do when the tach is in my hand.

I aim for about 200 rpm and about 20 degrees of dwell on the 8-cyl. scale. Double them to get the 4 cyl. numbers.
 
i had 3 from garage sales. they all read differently i deiced the one that looked to be in the right area to be the most accurate.
 
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