Ammeter to Voltmeter...who does it?

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I will be doing all the same mods on my sons 69 notchback. The only change I made in my wiring in the last schematic pic is I still ran the wires through the bulkhead connector since the whole output load of the alternator isnt going through there anymore, and is essentially split through 2 feed wires to the dash. I even have the sun volt gage at the ready for when the time comes to redo his dash.
 
Things you need to know... A solid state regulator grounded to inst' housing only is not chassis grounded until panel is attached to dash with screws. If you turn ignition switch on while panel dangles from harness connectors, or if that regulator looses ground for any reason, it will pass full 12 volts out to the gauges. Some retail regulator packages have ground fault protection built in but... they cost more. If you buy the one with flashing LEDs you may as well mount it near the fuse box or somewhere so it can be seen. It don't have to be on the back of the inst' panel.
Since a volts gauge will need a ground wire also, best to create a ground harness. Anchor it at lower screw at center gauge pod. Male and female terminals for service disconnect about 3 inches of wire beyond the anchor. Best place to terminate this ground wire is behind left kick panel. Best factory example of all this is at the heater case/blower motor ground.
No need to open the fuel gauge to disable that original limiter. Simply lift the gauge and place a layer or 2 of electric tape over that slither of metal on its backside to isolate that limiter from ground. The blue wire with white tracer supplies 12 volts to nothing more than the limiter. So take it out of the round connector and route it to the replacement regulator. 12 volts no longer goes to fuel gauge. 5 volts can find no other path than through the gauge and sender just like the other 2 thermal gauges. Done.
 
Redfish, that's a great solution on the isolating the voltage regulator, however I am tapping my 12V off the gas gage 12v feed stud. Not sure how that still isolates the original IVR unless you pop it apart and at least clip the black wire and bend the points apart so they dont touch. I did forget to mention that extra ground. What I did with my panel was add a grounding stud, and an extra wire that will be attached to the lower LH side of the dash at the mounting screw that holds the dash to the body.
 
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If a rally dash cluster, draw a clocking line on the back of the gas gage face to the gage housing so you can line it up putting it back together. Usingg a miniature set of wire cutters (dykes) carefully pry the crimps holding the gage face to the housing and remove the face. You will be staring at pic #1 carefully dewire the points regulator inside the gas gage and leave the 12V feed stud intact on the back and make a solid state IVR. Will cost about $7 in electronics store parts. That 12V feed stud provides a 12V feed to the new external IVR and a 12V feed to your volt gage.

Also no light will bleed thru the cut out. I put aluminum tape over the hole to keep dust out. I also used flexible and dimmable 5630 LED light strip to line the gage housing. You could replace the illumination bulbs with hi bright LEDs and get the same or similar look. The strip light is peel n stick, and I ran the wires to a bulb socket. Available at evilbay in many colors. Super inexpensive.Typically about $6-$8 per 5 meters lol. That's like 13 feet.

The ammeter bypass is more than just connecting the 2 wires together. However the rest of that mod is done at the engine side of the firewall since it bypasses alternator output to the battery and (bypasses the bulkhead connector). Last pic is the bypass. One above it is unbypassed.

Take your circuit boards and solder the wiring harness pins pins to the copper tracings on the board, then take small brass brads, cut them short to fit down inside the circuit board pins allowing the pin head to overlap the back of the pin where its crimped. Either JB weld them in or solder them in to prevent to pin from loosening and pulling out.

This should just about fix everything that's fucked about the rallye dash cluster.

Hope this helps
Matt

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I just had a thought probably a stupid one. But on your IVR schematic why should the capacitor be rated 15v or more in a 12 volt system, that when operating at a charge is around 14 volts?
Things that make you go hmmm.
 
I personally don't care what approach/method is taken. I didn't start the misinformation on the internet so I don't have to correct it. My only goal is help the "do it yourselfers" to understand what is and isn't required.
The fuel gauge and/or limiter are not relevant in this amp to volts gauge thread anyway. Good luck to all.
 
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I just had a thought probably a stupid one. But on your IVR schematic why should the capacitor be rated 15v or more in a 12 volt system, that when operating at a charge is around 14 volts?
Things that make you go hmmm.
Volt rating of the capasitor could be a billion. Any value above 12 volts works.
 
My points... First; no actual need to open this fuel gauge.
Second; The switched 12 volt wire to this instrument panel serves no other purpose/item/feature than the limiter. There is no reason to have a 12 volt wire routed to a fuel gauge. the wire and its terminal will fall right out of the round connector. Route it directly to the regulator, wherever it may be located.
Those who open the gauge and simply bend the thingy and don't isolate the gauge from chassis ground can and have had a 5 volt back feed leak though the remains of the limiter. Most will use needle nose pliers to bend the thingy. In doing so they have broken the insulation on the limiters winding shorting it to the beam its wound on. Some portion of that 50 ohms of winding is now shorting 12 volts to ground.
I personally don't care what approach/method is taken. I didn't start the misinformation on the internet so I don't have to correct it. My only goal is help the "do it yourselfers" to understand what is and isn't required.
The fuel gauge and/or limiter are not relevant in this amp to volts gauge thread anyway. Good luck to all.
I used the 12v fuel gage feed stud as a convienent way to jump 12V to the external mount solid state IVR, and to provide a 12V feed to the volt gage. My internal IVR is completely removed from the gage. The stud left behind is originally fed 12V from the pin on the circuit board. I stand by what I did and how I did it. Many different ways to do this. I gave him multiple options since rallye dashes are a *****, and you only want to do all this stuff one time and close it up.
 
So, not wanting to read this WHOLE thread, is there a member on this site who does the conversion? I have two I would like done.
 
So, not wanting to read this WHOLE thread, is there a member on this site who does the conversion? I have two I would like done.
What instrument panel(s)? This conversion isn't possible in some of them. Not enough space inside the housings.
 
If a rally dash cluster, draw a clocking line on the back of the gas gage face to the gage housing so you can line it up putting it back together. Usingg a miniature set of wire cutters (dykes) carefully pry the crimps holding the gage face to the housing and remove the face. You will be staring at pic #1 carefully dewire the points regulator inside the gas gage and leave the 12V feed stud intact on the back and make a solid state IVR. Will cost about $7 in electronics store parts. That 12V feed stud provides a 12V feed to the new external IVR and a 12V feed to your volt gage.

Also no light will bleed thru the cut out. I put aluminum tape over the hole to keep dust out. I also used flexible and dimmable 5630 LED light strip to line the gage housing. You could replace the illumination bulbs with hi bright LEDs and get the same or similar look. The strip light is peel n stick, and I ran the wires to a bulb socket. Available at evilbay in many colors. Super inexpensive.Typically about $6-$8 per 5 meters lol. That's like 13 feet.

The ammeter bypass is more than just connecting the 2 wires together. However the rest of that mod is done at the engine side of the firewall since it bypasses alternator output to the battery and (bypasses the bulkhead connector). Last pic is the bypass. One above it is unbypassed.

Take your circuit boards and solder the wiring harness pins pins to the copper tracings on the board, then take small brass brads, cut them short to fit down inside the circuit board pins allowing the pin head to overlap the back of the pin where its crimped. Either JB weld them in or solder them in to prevent to pin from loosening and pulling out.

This should just about fix everything that's fucked about the rallye dash cluster.

Hope this helps
Matt

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This question is one of curiosity more or less about how electricity works?
On the ammeter by pass schematic diagram B.
In the diagram, wire from the alternator goes through a 14 gauge fusible link to the relay and then from the relay through a 16 gauge fusible link to/through bulkhead connector.
Why the need for different fusible sized links in their perspective locations?
Which way/wire from the splice, after the 16 gauge link (red or black) would the electricity take to say the headlights, or the 3 way splice to be more precise?
Also Does this mean that all the power going to those 3 components (headlights ignition and fuse box goes through a 16 gauge (15 amp) fusible link?

Excuse my ignorance of electricity, maybe others are curious about this too.
 
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The 14 ga fuse link protects the alternator output wire which on a stock system is about 10 gage Fusible link should be 4 sizes smaller than the circuit it protects and about 6" long. The 16 gage link protects the wiring going inside the car. They are 2 seperate circuits. One feeding the battery, one drawing from it. Both wiring circuits use the starter relay lug as a power point out of convenience. What I did differently since I installed a larger alternator was to use marine grade 8 gage wire, with my own 12 gage fuse link. My alternator wire goes straight to the battery with a fuse link between it and the battery + terminal.

Pico wiring products sells fuse link wire in bulk length and you can put your own ring terminal ends on the fuse link wire and make your own.

The red and black wires going through fire wall both provide equal voltage power draw going into the car. It's not one or the other. Think of it like a stream with a Y and equally sized tributaries branching off, the water will flow an equal amount through both tributaries.
 
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The 14 ga fuse link protects the alternator output wire which on a stock system is about 10 gage Fusible link should be 4 sizes smaller than the circuit it protects and about 6" long. The 16 gage link protects the wiring going inside the car. They are 2 seperate circuits. One feeding the battery, one drawing from it. Both wiring circuits use the starter relay lug as a power point out of convenience. What I did differently since I installed a larger alternator was to use marine grade 8 gage wire, with my own 12 gage fuse link. My alternator wire goes straight to the battery with a fuse link between it and the battery + terminal.

Pico wiring products sells fuse link wire in bulk length and you can put your own ring terminal ends on the fuse link wire and make your own.

The red and black wires going through fire wall both provide equal voltage power draw going into the car. It's not one or the other. Think of it like a stream with a Y and equally sized tributaries branching off, the water will flow an equal amount through both tributaries.
Ok great analogy on the stream bit, very easy to visualize.
I just did a google search I learned something new just now.
I always thought a fusible link was just a normal wire with a fuse inline with it. I did not realize that it is actually just a wire itself. Cool.
 
Ok great analogy on the stream bit, very easy to visualize.
I just did a google search I learned something new just now.
I always thought a fusible link was just a normal wire with a fuse inline with it. I did not realize that it is actually just a wire itself. Cool.

What the Y does is it also takes a bit of load off the bulkhead connectors since its splitting up the power requirements through 2 wires. The schematic B shows the 2 wires bypassing the bulkhead connections altogether and just being straight through. This is not really necessary when you do the alternator direct to battery bypass, and use new or really cleaned up bulkhead connectors at those 2 firewall connections, and apply dielectric grease to the pins to keep moisture out that will corrode the contacts

On police package cars chrysler did just that. Drilling 2 holes in the firewall and installing rubber grommets then running the leads through the firewall bypassing the bulkhead connector. Police cars had more powerful alternators required to run the lights, and radio gear. Chrysler knew this was a weak link with a 120A or greater alternator and so bypassed it at the factory on police vehicles.
 
Also switching over to LED everything where possible will take a bit of load off your wiring. I am waiting for a nice efficient LED headlight to come along that looks like a sealed beam. Not a fan of these Halo looking lights or the bkack googly eyed looking ones.
 
Ok great analogy on the stream bit, very easy to visualize.
I agree. Well explained.

On police package cars chrysler did just that. Drilling 2 holes in the firewall and installing rubber grommets then running the leads through the firewall bypassing the bulkhead connector. Police cars had more powerful alternators required to run the lights, and radio gear. Chrysler knew this was a weak link with a 120A or greater alternator and so bypassed it at the factory on police vehicles.

Close. What I've seen on the older systems is one grommet with the ammeter feeds. This wasn't police per se. It was for various applications that were getting the 59, 60 amp Chrysler or any of the Leece-Neville alternators. There were various flavors of this scheme, but the idea was the same in all.

As you describe, the concept was to split the stream. On some it was done on the engine side, using a single post junction block. On others this was done on the ammeter's alternator connection (stud).

The ones with the junction block continued to use the standard bulkhead connection for the alternator feed.
By that decision, it appears the load they were most concerned about was the recharge of the battery. This is where on some configurations we see 8 or even 6 gage wires and a 10 or 12 gage fusible link.

Here's a Leece-Neville one from the '73 Dodge FSM
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Skim through this to see another way it was done. In this case, they didn't want to use the bulkhead feed at all. Probably because that defroster grid pulls alot of current just by itself.
How rare is electric rear defrost?
 
75 Ford F250 and my 64 Valiant.
I know the SunPro volt gauge will not fit in that early A-body housing. I assume all aftermarket volt gauges are about the same. I can't help. A ford truck forum might have help with that one.
 
If a rally dash cluster, draw a clocking line on the back of the gas gage face to the gage housing so you can line it up putting it back together. Usingg a miniature set of wire cutters (dykes) carefully pry the crimps holding the gage face to the housing and remove the face. You will be staring at pic #1 carefully dewire the points regulator inside the gas gage and leave the 12V feed stud intact on the back and make a solid state IVR. Will cost about $7 in electronics store parts. That 12V feed stud provides a 12V feed to the new external IVR and a 12V feed to your volt gage.

Also no light will bleed thru the cut out. I put aluminum tape over the hole to keep dust out. I also used flexible and dimmable 5630 LED light strip to line the gage housing. You could replace the illumination bulbs with hi bright LEDs and get the same or similar look. The strip light is peel n stick, and I ran the wires to a bulb socket. Available at evilbay in many colors. Super inexpensive.Typically about $6-$8 per 5 meters lol. That's like 13 feet.

The ammeter bypass is more than just connecting the 2 wires together. However the rest of that mod is done at the engine side of the firewall since it bypasses alternator output to the battery and (bypasses the bulkhead connector). Last pic is the bypass. One above it is unbypassed.

Take your circuit boards and solder the wiring harness pins pins to the copper tracings on the board, then take small brass brads, cut them short to fit down inside the circuit board pins allowing the pin head to overlap the back of the pin where its crimped. Either JB weld them in or solder them in to prevent to pin from loosening and pulling out.

This should just about fix everything that's fucked about the rallye dash cluster.

Hope this helps
Matt

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Thanks for all that info again.
I am curious about the Noise Suppressor and whether or not you replaced/relocated it or simply eliminated it?
Is it not needed to cancel unwanted noise feedback through the radio and/or speaker? Or what was it's purpose?
 
Glad to help. Unsure what its purpose was, probably radio noise, however I think with electronic ignitions and modern radios it's probably not needed. I plan on run ing a radio delete, and my car came that way from the get go, so it never had one anyways
 
I know the SunPro volt gauge will not fit in that early A-body housing. I assume all aftermarket volt gauges are about the same. I can't help. A ford truck forum might have help with that one.
Slightly off topic, I have a '64 Valiant stick shift. I believe the auto trans models used the space next to the wiper and light switch for shifter control. Is there room to put a pair of gauges in that panel?
 
here is mine,did it last spring.works great

if you’re still on the board Mike I’d love to see the final picture. I was curious whether the top of those numbers is cut off on you reassemble.

it looks a bit bigger than the original gauge.
 
The reason I ask I because unless it is repositioned I think a 2 inch gauge may be too big for 1973.
 
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