Another voltmeter vs. ammeter thread

[lippy]

I understand the safety advantages of a voltmeter vs. an ammeter. I'm probably going with a 70A alternator (slight bump over the "standard" 60A one), and ERA tells me my wiring and ammeter can handle it. Still, I'm thinking of replacing my ammeter with this voltmeter: http://www.summitracing.com/parts/sw...FWXZQgodkmwANQ because it's generally safer and pretty easy to wire at this point, with the dash off and engine out. I would wire it in such a way that would enable me to use a larger alternator in the future.

How many of you have actually switched to a voltmeter? Is this worth the effort and cost (not much, maybe $70 total) or is the ammeter a non-issue?

[sllib]

My ammeter just stopped working. After asking around and considering the car wasn't even on the road yet I ordered a voltmeter from Summit that matched my other guages. I'm happy with that.
Bill

[Grubby]

Ammeter works. I can tell if I am charging or discharging.

If I had a no cost choice during build it would have be voltmeter.

Why change if it isn't broken?

John

[vatdevil]

Yes, worth it. Ammeter indictes which direction the system is heading. Voltmeter indictes where its at. Better info in my opinion.

[Jaydee]

Voltmeter is the real countdown to when your car will die. A amp meter just tells you when it stops charging.
JD

[racco]

I removed a near melted amp gauge and installed a volt gauge

looks near identical

don't miss the amp

[RICK LAKE]

Lippy, give me a call in the evening. Amp gauges are period correct. They do work to some degree. With a 70A or higher charging system you have PASSED the safe ampage for this meter and more important the insolators on the rods. Volt gauge work just as well WITHOUT making it handle the amps. Lippy wire the 2 main wirings togeather and add a pintail lead to the volt gauge. You need a ground wire. The bulb light should just plug into the back of the new gauge. SW gauges sell a volt meter but it has color on the face. Ps I melted the insolators in my car after 12 years of racing. It's only plastic and melts or burnt over time. the connection where tight. I did the same thing with a 72 CJ5 jeep. IT has the same basic wiring harness for a 38-60amp alt. IMP a voltage gauge works better than an amp gauge for reading charging of the system and battery voltage. IF the amp meter was the best thing, they still would be in new trucks and some cars. Rick L.

Grubby with your car being older than mine, you might want to pull the dash and check out the insolators on your amp gauge. I have seen a couple of dash fires and it was not pretty. Plastic does break down, it's not a water bottle. Just my thoughts and hate seeing a beautiful car burnt by a 5 cent plastic sleeve. I still have my burnt gauge sleeve. Wish I could sent a picture of it. ERA assemblied my dash and the connections where tight. I am using more ampage in my car than most with extra fans, fuel pumps, and FI system. This is my change of the charging system and not ERA.

[lippy]

I decided to move forward with the voltmeter. I will wire it as follows: Wiring changes for a voltmeter, and use even thicker wire (AWG 6/8) in the engine compartment. Of course, my current crimpers can't handle these terminals, so I had to buy a new crimper too (Wiha 32841). An excuse to buy a new tool isn't entirely a bad thing.

I also realized my old Vette has an Ammeter, though that car has a generator and probably puts out 25A +/-. Either way I'm going to check the circuit and connections carefully.

[strictlypersonl]

Lippy,
Check out the ERA owner's section for the latest wiring instructions for your car. They include instructions toward the back for initially wiring the voltmeter (as opposed to an update method). There's a new wiring diagram too.

[lippy]

Bob,

I went there and found the wiring diagram but not the instructions. Could you point me in the right direction or send a PM?

Also, If I use AWG 6/8 wires under the hood and wire it this way with a voltmeter, how large of an alternator could the circuit handle? Thanks,

Lippy

[strictlypersonl]

Rushing too much at the end of the day...
Link fixed this AM.

[289FIA]

Originally Posted by strictlypersonl

Lippy,
Check out the ERA owner's section for the latest wiring instructions for your car. They include instructions toward the back for initially wiring the voltmeter (as opposed to an update method). There's a new wiring diagram too.

Very timely post Lippy. My dash is out and now would be the time.

Bob, any ammeter to voltmeter instructions posted on the ERA site for the FIA?

Thanks,
289FIA

[lippy]

Originally Posted by 289FIA

Very timely post Lippy. My dash is out and now would be the time.

Bob, any ammeter to voltmeter instructions posted on the ERA site for the FIA?

Thanks,
289FIA

Go to the owner's section on the website and there should be a page on voltmeter installation toward the back of the latest wiring instructions, and a diagram for wiring with a voltmeter.

I did it last night with my daughter. Piece of cake, that is if it turns out to work.

[strictlypersonl]

Unfortunately, some of the wiring colors and paths of the FIA are different than the 427. Until I work out something "official" for the FIA, you can probably compare the FIA wiring diagram to the 427's and figure out which large plugs to switch around.

Since the connection to the ammeter is a separate jumper, you could even just take the Siamese'd connector apart and loop one plug around into the other to bypass the ammeter.