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A little help with RCCI tach
I will be installing my RCCI tach in a couple days. Bob says you can use the original tach wires to power the tach, my resistance wire is one of the 2 wires that plugged into my tach, does this mean this tach will run off the 9 some odd volts that I get from that wire? Or is the other wire 12v, and this is the start of the resistance wire? I really want to get this right! Thanks gents!!
The wire from the solenoid to the tach is non-resistance, 12V. The wire to the coil is the resistance wire, 9V. When I installed mine, I made a jumper wire that connected to the dash plug and had a lead that came off to power the tach. I ran a wire to the dash support for chassis ground and a new wire to the coil ground on the distributor.

What Steve said ^.
The screw that holds the IVR to the cluster is also a good ground point.


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I took the 12v off the switch terminal post on the fuse box and grounded to the firewall. My tach signal comes off the MSD box but you can also take it from the coil.

351C 4V cc heads, 10.5 : 1 CR, 290 Herbert cam, Flat top forged pistons, forged connecting rods, Atomic efi,
C6 with Gear Vendor overdrive, 3.89 Tru Trac, Hooker Super Comp with 2 1/2" Pypes Exhaust.        

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Instead of hooking the original resistance wire back up, can I just run a 12v line off the solenoid wire from the tach out to the coil and then run a flamethrower 2 coil? Does the FT2 work with the original Pertronix triggering unit? I am going to change to a Duraspark unit when I drop the new motor in and I want to run everything off a full 12v switched.
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