Canepa Twin . . . where do you get your hands on such rare ditties . . ?

What you have is a Nash twin-plug dizzy converted by Bill Fisher's speed shop for use on a Chevy Six. This is documented on page 63 of his speed manual. The setup assumes a Stewart Warner tach-drive between the dizzy and the cam gear/oil-pump dog.

The original intention of Nash engineers was to have two plugs per cylinder firing at nearly the same time from separate coils - suffice to say they were years ahead of the boys at MSD in El Paso.

Fisher's idea was to leverage the setup for high RPM by using half of the dizzy for one set of cylinders and half for the other set. With two coil/condenser circuits and the offset rotor the 'single plug' firing order was based on every fourth hole in the dizzy head. This setup allowed for a much less crowded dwell angles and much higher RPM because each coil was only subject to 'breaking' half as often in a traditional Delco six hole dizzy.

This could be made to work on a Jummy or Chevy. I would go back to your numerous bins in search of an SW mechanical tach drive . . .

Nice piece.

regards,
stock49

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