Speedhut Gauges

[hrosenthal]

The instructions provided with my Ron Francis harness show a different set of gauges than I have.

I have the Speedhut gauges which require less wiring.

The gauges use two distribution cables (for power and dial lighting) which easily snap into the gauges serially.

After that, there is no clear instruction on how to connect the gauge wires to the dash harness (or even if I should bypass the harness altogether).

Any guidance is appreciated.

Thanks

[edwardb]

Agree the instructions are a little sketchy for this combination. Use the interconnect wires supplied by Speedhut to daisy chain the gauge lighting and power circuits. Used the supplied Ron Francis dash harness. There is a light circuit that goes through a dimmer for the backlighting, and another that is for the lit needles. Both connect to a which dash light wire in the harness. The gauge power cable goes to the brown gauge feed. Then of course each gauge has it's own sending wire(s) and grounds. All the harness wires are clearly marked. The Speedhut instructions explain the gauges.

I know this doesn't give any details, but mine looked like this when done. For me, the Ron Francis dash harness leg worked best point to the center as pictured. With the dash installed, curves around and plugs into the main harness. May not be the same for you. Just do what works best.

http://i867.photobucket.com/albums/ab234/edwardb123/Factory%20Five%20Mark%204%20Roadster%20Build/Electrical/IMG_2337_zps4fb545bf.jpg (http://s867.photobucket.com/user/edwardb123/media/Factory%20Five%20Mark%204%20Roadster%20Build/Electrical/IMG_2337_zps4fb545bf.jpg.html)

[hrosenthal]

Agree the instructions are a little sketchy for this combination. Use the interconnect wires supplied by Speedhut to daisy chain the gauge lighting and power circuits. Used the supplied Ron Francis dash harness. There is a light circuit that goes through a dimmer for the backlighting, and another that is for the lit needles. Both connect to a which dash light wire in the harness. The gauge power cable goes to the brown gauge feed. Then of course each gauge has it's own sending wire(s) and grounds. All the harness wires are clearly marked. The Speedhut instructions explain the gauges.


So I'll wire each gauge to it's own sender directly and won't bother with the harness except for the power and ground.

That seems straightforward enough.

I see that you wired the set button to one gauge and attached it under the dash. Do you need to remove the dash to reset the clock?

Thanks

[edwardb]

No, use the sender wires from the dash harness for the gauges. Sorry I didn't make that clear. They're all there. When done, everything goes through the dash harness except the headlight switch and the ignition switch, which have their own connectors off the main harness. If necessary, the dash can be removed by unplugging all the connectors on the harness. The wires for the actual sending units all come out of the main harness.

I installed one push button permanently along the front edge of the dash for the speedo. Needed for calibration and also for trip odometer reset. I also put the gauge dimmer knob along the bottom of the dash. I made up another push button cable for the clock. The button is inside the glovebox. You can see the cable coming out of the clock going over to the corner of the glove box. It's the furthest LH gauge in the pic. All the other gauges I calibrated before the body was on and don't need cables permanently. If necessary in the future, I can reach the calibration jacks by reaching from under the dash. I've seen a couple builds where guys made up a little patch bay, and routed all the calibration jacks to a central point. Cool I guess, but not really necessary IMHO. Other than the clock and speedo, the rest are one time and done other than for service of some kind.



So I'll wire each gauge to it's own sender directly and won't bother with the harness except for the power and ground.

That seems straightforward enough.

I see that you wired the set button to one gauge and attached it under the dash. Do you need to remove the dash to reset the clock?

Thanks

[Jeff Kleiner]

The Speedhut/FFR Classic gauges use 2 wire senders while the RF harness is set up for one wire. You can use some of the redundant or unused wires in the harness for the second conductor but I recommend doing kind of a hybrid incorporating the long Speedhut pigtails. You'll need to power up all of the gauges on their red wire by connecting them to the brown "gauge feed" wire in the harness. Also connect the black "ground" wire in the dash harness to each of the gauges' black wires. You will carry the tachometer signal from the coil on the purple "coil-tach" wire that runs all the way through in the sending units subharness. The speedo signal comes through the green and gray wires which will join the yellow/red and yellow/black wires on the gauge. Polarity is not important as it is only counting pulses. For the coolant temperature and oil pressure gauges run the pigtail with the yellow/red and yellow/black wires to their respective senders. Once again polarity is not an issue because these are simply reading resistance. The voltmeter has no sender, the gauge power and ground give it all it needs. Fuel gauge connects to the light green "gas sender" wire. I recommend powering the clock from the red "radio memory" wire. That will get everything working!

Next move on to gauge lighting and their daisy chain. The white wire from all of the gauges connects to the RF harness white "dash lights" wire. If you have the seperate dimmer module the white harness "dash lights" wire connects to the input of the dimmer; the dimmer's black ground connects to the black harness ground. From there the dimmers output snaps into the connectors for the lighter gauge wire. It seems redundant but is this way because the needles are lighted independently from the gauge face and are not dimmed. If you do not have the dimmer module then the small white wire at the end of the snap together chain also connects to the harness white "dash lights" wire. By the way, before you drive yourself crazy thinking something is wrong... the hands on the clock are not lighted.

Hope that helps,
Jeff

[hrosenthal]

The Speedhut/FFR Classic gauges use 2 wire senders while the RF harness is set up for one wire. You can use some of the redundant or unused wires in the harness for the second conductor but I recommend doing kind of a hybrid incorporating the long Speedhut pigtails. You'll need to power up all of the gauges on their red wire by connecting them to the brown "gauge feed" wire in the harness. Also connect the black "ground" wire in the dash harness to each of the gauges' black wires. You will carry the tachometer signal from the coil on the purple "coil-tach" wire that runs all the way through in the sending units subharness. The speedo signal comes through the green and gray wires which will join the yellow/red and yellow/black wires on the gauge. Polarity is not important as it is only counting pulses. For the coolant temperature and oil pressure gauges run the pigtail with the yellow/red and yellow/black wires to their respective senders. Once again polarity is not an issue because these are simply reading resistance. The voltmeter has no sender, the gauge power and ground give it all it needs. Fuel gauge connects to the light green "gas sender" wire. I recommend powering the clock from the red "radio memory" wire. That will get everything working!

Next move on to gauge lighting and their daisy chain. The white wire from all of the gauges connects to the RF harness white "dash lights" wire. If you have the seperate dimmer module the white harness "dash lights" wire connects to the input of the dimmer; the dimmer's black ground connects to the black harness ground. From there the dimmers output snaps into the connectors for the lighter gauge wire. It seems redundant but is this way because the needles are lighted independently from the gauge face and are not dimmed. If you do not have the dimmer module then the small white wire at the end of the snap together chain also connects to the harness white "dash lights" wire. By the way, before you drive yourself crazy thinking something is wrong... the hands on the clock are not lighted.

Hope that helps,
Jeff


Thanks so much for this detailed description. Tonight I labeled all the wires and tomorrow I will connect them.