Amp gauge or Volt gauge?

I am looking at the under dash triple gauge kits and I see some have amp gauges and some have volt gauges. Which would I want for my street SBC powered "60 Falcon.

 

volt gauge

 

Ammeter is 'old school' and 'period correct', but requires that you run the entire electrical system load (except for the starter) through the gauge to be accurate. This puts a high-current wire inside the car, and a gauge failure kills everything.

A voltmeter can be tapped in to any switched voltage source and uses low current; much safer.

 

I'd go with volt .

Depend on 100% period correct

And if you want to know how much you have or how much you are using

 

volt gauge

 

Volt meter is MUCH safer Amp gauge can be fire hazard if a malfunction occurs.

 

Thanks guys, I will go with the volt gauge.

 

Getting opinions is good but you need to make your decision based on what "you" are wanting to know.
Volt gauge - shows output of charging system
Amp gauge - shows draw on system
You can have a charging system show things are charging well on a Volt gauge but you don't have an indicator if it is keeping up with electrical demand. An Amp gauge will tell you if the charging system is keeping up with the demand or not. A fire hazard is only a possibility with an Amp gauge if a fuse or fuseable link is not used.
Hope this helps.

 

if you wanna be ultra period correct you can get a volt gauge and have the face reworked to read "amps" it can say anything you want as long as you understand what it is no problem.

 

I'd say if the voltmeter is showing much over 13.4 volts as each additional accessory the charging system is keeping up with demand just fine. If turning on the heater fan, headlights, rear window defroster and 100 watt stereo makes the voltage drop below 13.X an ammeter would show zero or negative charge too.

Once an internal cable connection between regulator and alternator went "bad" and smoked the ignition module in about a second. the no start condition was obvious.
Once I had a regulator fail "on". The headlights were a touch brighter which caught my attention. A diagnostic voltmeter reported over 15 volts, which would have been in the red zone of OEM dash units. An ammeter should have shown relatively high charging amps. Fortunately the ECU survived fine.

 

I put a voltmeter movement in an ammeter on my daily driver. It had a shunt type ammeter and didn't work anymore, and I put a larger alternator on and had to redo the wiring anyway.

I put the needle with 0 amps being 12 volts.

It works well.

 

Volt meter. Griffin Auto Electic