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Tac wiring

Gregg DeGeorge

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Location
Naugatuck Ct 06770
Hello all putting my 70Roadrunner back together,it has a Ralley dash how is the tach wired ?Car has a 440 with mopar HEI ,I put the dash together outside the car but tach doesn’t move at all I had dash gages gone threw before I put them in .just looking for basic wiring of where the wires go . Thanks
 
Hello all putting my 70Roadrunner back together,it has a Ralley dash how is the tach wired ?Car has a 440 with mopar HEI ,I put the dash together outside the car but tach doesn’t move at all I had dash gages gone threw before I put them in .just looking for basic wiring of where the wires go . Thanks

I made the tac wiring bold dark grey in these schematics. Wire comes from the condenser side of the distributor to the negative side of the coil. Your grey w tracer wire also goes on the negative side of the coil. Then it passes through the firewall and connects directly to the tach. Blue wire from the tach goes to a fuse. And lastly the light for the tach should be an orange wire from an orange multi connection harness.
70BelvedereGTXSatelliteRoad RunnerA.jpg
70BelvedereGTXSatelliteRoad RunnerB.jpg
 
Last edited:
I made the tac wiring bold dark grey in these schematics. Wire comes from the condenser side of the distributor to the negative side of the coil. Your grey w tracer wire also goes on the negative side of the coil. Then it passes through the firewall and connects directly to the tach. Blue wire from the tach goes to a fuse. And lastly the light for the tach should be an orange wire from an orange multi connection harness.
View attachment 964282 View attachment 964283
. Thanks just getting my car back together think the tach harness is mia or never got run through the firewall ,there’s nothing hooked up to that gray tracer wire by eng harness plug
 
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