Windsor64
New Member
Hi everybody, I would like to upgrade my 35 A alternator to 60 A and convert my ammeter to voltmeter, what are the best places for this conversion ?
Thanks Alain
Thanks Alain
Ammeter to voltmeter conversion
- Thread starter Windsor64
- Start date
Ripinator
Old Man with a Hat
Unless you are gonna replace / upgrade all the associated wiring, I don't think you wanna do this.
Windsor64
New Member
This is what I want to do while removing the dangerous ammeter.
dart4forte
Well-Known Member
wish4hemi
Member
Redline Gauge Works would be the most professional route.
Redline Gauge Works Refurbs A Retro Chrysler Cluster - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
Or you can try to do it yourself.
Gallery: How to Convert an Ammeter to a Voltmeter on the Cheap - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
Redline Gauge Works Refurbs A Retro Chrysler Cluster - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
Or you can try to do it yourself.
Gallery: How to Convert an Ammeter to a Voltmeter on the Cheap - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
John Kirby
Active Member
I found the biggest problem is the firewall connections. They are not sealed and very prone to corrosion. Gets worse as the amperage goes up. My solution was to bypass the connector and route the battery and alternator wires through the firewall directly. I drilled holes and used rubber grommets along with solderable butt splice connectors under the dash. Heat shrink tubing sealed them up and prevents shorts. A mini butane torch works for soldering. Don't use acid core solder.
Along with this, adding headlight relays eliminates the high current connections through the connector. Your lights will be very bright afterward. Connect the relay source to the alternator side to keep the gauge working as original.
The other 50% is grounding. All the external lights depend on the sheet metal for a ground. The path goes from the light to the mounting bolts to the ground strap at the back of the engine through t the engine to the battery ground. Improving this path will fix a lot of electrical gremlins. Mounting nuts for lights break the paint surface and promote rust at these points.
Rust from salt, etc is not a friend of electricity. All vehicle makers built cars this way in the c-body era. They expected the car would be in a junk yard within 5-6 years and designed accordingly. If you're doing a tear down resto it is a good idea to weld 1/8" bolts to the sheet metal in these areas and make wire connections to the light housings for a secure ground. This is standard procedure on new cars for reliability.
Along with this, adding headlight relays eliminates the high current connections through the connector. Your lights will be very bright afterward. Connect the relay source to the alternator side to keep the gauge working as original.
The other 50% is grounding. All the external lights depend on the sheet metal for a ground. The path goes from the light to the mounting bolts to the ground strap at the back of the engine through t the engine to the battery ground. Improving this path will fix a lot of electrical gremlins. Mounting nuts for lights break the paint surface and promote rust at these points.
Rust from salt, etc is not a friend of electricity. All vehicle makers built cars this way in the c-body era. They expected the car would be in a junk yard within 5-6 years and designed accordingly. If you're doing a tear down resto it is a good idea to weld 1/8" bolts to the sheet metal in these areas and make wire connections to the light housings for a secure ground. This is standard procedure on new cars for reliability.
cbarge
World Famous Barge in a Budget
Well said!!
I am not even going to attempt to comment on this thread LOL!!
The wiring for the charge circuit on your car is designed for a 35 amp alternator. The wiring gets brittle with age. It would be helpful to know if the car in question is a '64 Windsor.
Switching to a 60 amp alternator without upgrading all of the wiring in the charge circuit is more dangerous than the stock ammeter. This is also a swap that creates a domino effect.
If this is what you want to do, you at least need to:
- Upgrade all of the wiring in the charge circuit
- Do an ammeter gauge bypass (search this site for details)
- Upgrade to the '70 & up voltage regulator or use this one;
Mopar Voltage Regulator - Electronic Solid State with Correct Restoration Look | eBay
- Clean and check all of the bulkhead connectors
- Run separate wiring for your voltmeter
A headlamp relay conversion would also be beneficial.
Why not just go with a 45 or 50 amp alternator?
Why do you feel that you need the 60 amp alternator? Unless you are running electric fans or a power draining mega watt stereo system or fuel injection you should not need a 60 amp alternator.
live4theking
Old Man with a Hat
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Great wisdom shared above...
Don't make the fix worse than the problem.
Don't make the fix worse than the problem.
John Kirby
Active Member
My 66 has electric fans, a 540 watt stereo and fuel injection.
You are correct. In a bone stock c-body there isn't much need to upgrade the charging wiring, except for the ammeter/firewall connection. And headlight relays.
My wiring adventure started with an 8 gauge alternator connection. and a 100 amp alternator. Measuring the voltage drop from the alternator with that update indicated way too much voltage drop and the battery was never getting a full charge. This was before blasting the stereo. So I added a junction terminal and changed the wire to 4 gauge oxygen free copper. That helped with the voltage drop. The terminal looks similar to this:
One side goes to ammeter through the firewall, the other is the alternator feed. On the alternator feed side I tapped off to a fuse panel mounted under the hood. The headlight relays, stereo system, fuel injection and fans are powered from there. The point of doing it this way is so the ammeter will remain centered when the engine is running and the battery is fully charged. If you connect everything to the battery, the ammeter will indicate it is constantly being charged, which is incorrect. The ammeter is supposed to only show current flowing in and out of the battery, nothing else.
This is why an ammeter is better than a voltmeter for showing an alternator fault. With a voltmeter, the battery will indicate nearly normal voltage until it gets drained enough to show a problem. By then you are within minutes of sitting on the side of the road. An ammeter will show a fault when it happens if you glance at it while looking at the gauges. So you have time to find a place to get off the road.
In the 70's Chrysler redesigned this with a calibrated piece of wire going from the alternator to the battery. two connections were made to it and the voltage across it was used as a current indication. Basically it is a current shunt eliminating the firewall connection problems.
Bvmarchisotto
New Member
Does anyone have anymore info on the needle that was glued on in the ammeter to volt meter gauge? I have everything needed to complete this but have some concerns about longevity and cutting the needle off the volt gauge to glue one on from a donor cluster. Was this glued over top of the needle or was it actually cut and glued end to end?
SA67NEWPORT
New Member
In my 67 Newport, I converted my ammeter to a voltmeter by removing the ammeter from the dashboard, gutting it and replacing the guts with a digital voltmeter of the correct dimensions that I found on ebay. I then cut a hole in the ammeter meter scale so the voltmeter would be centered on the scale and put the whole thing back in the car. I then connected the voltmeter wiring to the appropriate place and connected the ammeter wires together. to complete the circuit. The comments about the bulkhead connector and grounds are very much on point. In my car I also had a fuse box with not one good connection in it, so I had to replace that as well. If you want more details on the voltmeter I can provide
Bvmarchisotto
New Member
Thanks for reply. Yeah I would like to see what yours looks like and know more details on how you completed it. I like the idea of having the factory appearance but I am hesitance to cut the needle off my factory gauge to glue it to the volt meter. I would hate for the thing to fall off then have to figure out and alternative.
Thanks for all your input.
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