Any tricks for swapping out the amp gauge to volts?

RICK LAKE · #1 (**permalink**) 02-02-2009, 02:34 PM

Strictly Personal Bob the 70 amp setup in my car is not enough for keeping the battery fully charged with all the power drain from FI system, MSD box, 3 coolant fans, 2 duct fans. Want to swap out the gauge from amps to Volts. Have 130 Alt and kit for voltage regulator. Anything else needed for this change? Rick L.

strictlypersonl · #2 (**permalink**) 02-02-2009, 02:42 PM

The Q&D method is to connect the two wires currently

going to the ammeter and run a wire from the accessory terminal of the ignition switch to the voltmeter. That still means that you're running full current through the 10 gauge wires, and 100+ amps is really overloading that circuit. I'll figure out a better way to do it tomorrow at work. It will require some wire splicing at the firewall.

RICK LAKE · #3 (**permalink**) 02-02-2009, 02:47 PM

Bob my car is 428. Not sure about the wiring changes you have made over the last 10 years. I do have a full print out of the wiring setup. I will go to a #6 0r #8 gauge wire and a 125 amp fusable link in the alt output side. I don't want to fry the wiring harness or gauges. Rick

strictlypersonl · #4 (**permalink**) 02-04-2009, 05:27 AM

Still recovering from Monday. I'll post the instructions today. Watch this spot.

See this page.

I sent you a link to a wiring diagram that includes fuel injection and the voltmeter.

289FIA · #5 (**permalink**) 02-04-2009, 08:22 PM

Bob,

Would it be the same for a FIA car?

2121 is at the "factory" with the same requested swap.

Alex

strictlypersonl · #6 (**permalink**) 02-05-2009, 04:51 AM

The FIA would be similar. Are you going to use a high-amp alternator?

trularin · #7 (**permalink**) 02-05-2009, 06:37 AM

As long as the delivery wire from the Alt to the Batt is suitable, you should not have any problem.

If it is three wire ( Ford style ) it will be more stable with a 75 Ohm Excite resistor than the 180 Ohm Excite resistor.

Just my opinion.

Rick, if you need a 125 link, let me know, I think I still have some. And, the volt meter should be fine at the terminal block. If you wish, you can just remove the shunt and Amp meter.

289FIA · #8 (**permalink**) 02-09-2009, 08:47 AM

Bob,

I'm hoping a standard alternator (60amp) would be fine for MSD and perhaps a 12V power outlet. EFI is on the back burner for now.

Thanks,
Alex

patrickt · #9 (**permalink**) 02-09-2009, 08:51 AM

Quote:

Originally Posted by 289FIA

I'm hoping a standard alternator (60amp) would be fine for MSD and perhaps a 12V power outlet. EFI is on the back burner for now.

It will be. If you're like me, and you run the MSD, Heavy Duty puller fan, dual pusher fans, and plug a GPS or Blackberry charger in to the cigar lighter, you won't have any charging problems at all with the 60 amp.

Now if you start running stuff like Rick L., then that's another story....