Stock Smiths Tachometer

[LotusJoe]

Can someone who has a stock Smiths tachometer on a Twin Cam looks at the face and tell me if it has the initials "RVC" 

Thanks

[4129R]

Mine has RVI 1432/00.

[LotusJoe]

Mine has RVI 1432/00.

That's what I was thought. Since I run an electronic ignition I replaced my tach some time ago. I gave my original tach to a friend who is restoring a 67 Mini Cooper. He is also running an electronic ignition so the RVI will not work. Thank you looking.

 

[Bainford]

Joe, somewhere on this forum is a discussion on running electronic ignition. In that discussion a couple of guys mentioned that they had tach problems when switching to electronic ignition, and a simple solution to the problem was presented. If I can find the thread I'll post the link.

[Bainford]

There might be some useful info here http://www.lotuseuropa.org/LotusForum/index.php?topic=521.0

[BDA]

Interestingly, I had tach problems with my original ('73) tach with an Allison (light) ignition. When I replaced it with a Pertronix ignition, my tach worked fine.

[LotusJoe]

I have been doing some research on the various models of Smiths Tachometers. The one labeled RVI on the face (Like the ones on the Twin Cam) are wired to the positive side of the coil and have an internal loop that picks up the pulse signal from the coil. The ones labels RVC are wired to the negative side of the coil like most conventional tachs . The RVC tachs were used in Midgets, MGBs. I have found several on Evil-Bay and will try one of those on my friends Mini Cooper.

Here is the reference I found:
http://www.theminiforum.co.uk/forums/topic/135439-smiths-rev-gauge-wiring/

[jbcollier]

Mid production MGBs also used RVI tachs.  You can mod the wiring to work with most electronic ignitions.