Wiring - numerous questions

[racephotoman]

Probably the first of many questions:

I see the sensor wires going to the engine (sensors) and gauges. Gauges have connection for + and - (ground), OK, while sensor side wires have the same + and - wire, but the sensors themselves just a terminal for the +. Do I just bundled all the ground together and attach to the chassis? Just seems like an abundance of wiring in the engine compartment.

Does the TACH go to the negative of the coil?

Also, my alternator says it just needs one wire, while the harness going to the alternator has the large red, and smaller gauge brownish wire. Best to connect both, or just the red and disconnect the brownish from the ignition switch?

Not using the electronic speedometer, using a mechanical - just tape up the bare wire ends on both sides?

Any help is appreciated - thanks

Walter86969

[edwardb]

Assume you have the Ron Francis harness but not the usual Speedhut gauges? Always best to give at least that amount of information if asking about wiring. Also wouldn't hurt to know more about the engine setup you're using. But assuming RF harness and not Speedhut gauges:

- The RF harness most recent version has grounds for all the gauge sending wires because that's what Speedhut requires. Sounds like yours only use the positive wire to the sending unit and get the ground through the block. No issues. Don't bother with ground wires for the sending units into the engine compartment. Make sure you have the block properly grounded. At minimum, one from one of the starter mounting bolts to the frame. I usually add a second from the block itself to the frame.

- Traditional tach connection is to the negative side of the coil when not using an ignition or EFI module of some kind.

- Those three wires in your alternator harness are all connected together. If you pull back the insulation, you'll see where the two large red wires are joined. Just cut off what you don't need and connect the single wire.

- Yes you can cap the bare ends of the unused speed sensor wires. Good luck with that mechanical speedo cable. :p I sure don't miss those from back in the day.

[racephotoman]

Thank you - you are right about giving as much details as possible now in in the future. Yes I'm using the standard RF harness and the standard AutoMeter gauges that came with the kit. I'm getting confused because I installed a EFI setup on the engine and have to deal with those wires, and basically assume that they override the RF wire layout? (LIKE THE EFI HAS THIER OWN WIRE TO THE COIL - or hookup both ) Also, yes my gauges have a prong for "+," ground and sensor input, so figure using the wire marked "gauge" and a ground for the gauges - my problem is the leads going to the sensors also all have a separate ground wires while the sensors do not - so I was thinking to bundle them in the engine compartment and attach to a ground (engine block) - just seems like it's a lot of extra wires in the engine compartment for nothing?

I also installed the steering column which also potentially eliminates more wires on the RF harness.

Finally, the engine's alternator calls for a single line, so I would just eliminate the brown wire? My engine guy said to also run a wire from the alternator to starter - this seems weird.

Walter

[weendoggy]

What EFI setup? They will have instructions and their sensors will NOT be the same as the ones used for your gauges. i.e. coolant temperature sensor or CTS=(EFI), water temperature sender=(Autometer) and so on. Connection to "coil" depends on what your EFI system requires.

All your Autometer gauges can be "daisy chained" for the ground side, EXCEPT for the Voltmeter if you use one. The sender wire will come from the sender itself and on to the gauge. As for the wire to starter, he's assuming you're running a battery cable to the starter lug, which you will need.

More information will help get you answers.

[edwardb]

Thank you - you are right about giving as much details as possible now in in the future. Yes I'm using the standard RF harness and the standard AutoMeter gauges that came with the kit. I'm getting confused because I installed a EFI setup on the engine and have to deal with those wires, and basically assume that they override the RF wire layout? (LIKE THE EFI HAS THIER OWN WIRE TO THE COIL - or hookup both ) Also, yes my gauges have a prong for "+," ground and sensor input, so figure using the wire marked "gauge" and a ground for the gauges - my problem is the leads going to the sensors also all have a separate ground wires while the sensors do not - so I was thinking to bundle them in the engine compartment and attach to a ground (engine block) - just seems like it's a lot of extra wires in the engine compartment for nothing?

I also installed the steering column which also potentially eliminates more wires on the RF harness.

Finally, the engine's alternator calls for a single line, so I would just eliminate the brown wire? My engine guy said to also run a wire from the alternator to starter - this seems weird.

Walter

Can't add too much to what I already posted. If you have an EFI setup with a control box, it should have a tach connection and that's what you would use. Not the coil and certainly not both. Same answer on the sender wires. If you have single wire senders, you don't need grounds in the leads to the senders. The gauges themselves should be grounded. And the senders are grounded through the block as I described. The RF schematic shows how the brown alternator wire in the alternator harness is routed. For a 1-wire alternator, I've never used it. Only the one large red wire. I don't understand the wire from the alternator to starter you're being told to use. The RF harness gets the alternator feed elsewhere.

[racephotoman]

Yes, I figured/told just not use the extra "brown" alternator wire - as per suggestion will just disconnect it from the ignition switch and not use it
And yes, I'm confused about wiring as per suggestion from the engine builder from the alternator to starter - unless a reason for this surfaces, I won't. What bothered me was all the separate brown ground wires for all the sensors in the engine bay - yes, especially since the sensors as you mentioned are physically grounded and the meters grounded. Probably for a two terminal sensor perhaps? I will just tuck them up into the wire protection sleeve. I decided since I'm a novice at wiring, I'm going to start another thread covering the hookup between the RF harnesses and my Holley EFI . This way I'll walk through what I'm doing and include all my questions and your (forum) answers. This will definitely help me and possible future builders to use as a guide. So far, I did get great answers from all of you already and want to thank everyone so far.

Walter

[i.e.427]

Walter, you should also add your location to your forum info. Guaranteed there is another Factory Five owner in your area that would love to come over and help you through your wiring woes.

Frank