Alternator upgrade queston

[Hop Head]

I have a question about updating my electrical system on my 69 charger. I'm in the planning phase right now, and it looks like I'll be going with a kit from Ron Francis.  My question for you guys is about the alternator wiring, Ron needs to know what I'll be using. The car currently has the stock alt, but I want to upgrade for future additions.  Such as A/C, fuel injection, electric fans, and a headlights from Daniel Stern. If I install, lets say a 100A alt now, without all the new additions, will there be any problems.  I going to do the updates in phases, the first being the wiring.  Let me know what you think.  Thanks....Russ   

[Mopar Nut]

I have a question about updating my electrical system on my 69 charger. I'm in the planning phase right now, and it looks like I'll be going with a kit from Ron Francis.  My question for you guys is about the alternator wiring, Ron needs to know what I'll be using. The car currently has the stock alt, but I want to upgrade for future additions.  Such as A/C, fuel injection, electric fans, and a headlights from Daniel Stern. If I install, lets say a 100A alt now, without all the new additions, will there be any problems.  I going to do the updates in phases, the first being the wiring.  Let me know what you think.  Thanks....Russ   

Are you going to use a electronic ignition system too?

I would definitely upgrade to a 100 amp alt.

[Hop Head]

Yes, it's already been switched over.

[Pete in NH]

Hi,

It's good thinking to get into a planning phase as you are doing and ask questions. Essentially what you're undertaking is to turn a 40+ year-old electrical system into something that looks more like cars of today.

On your question about a 100 amp alternator, you're present alternator's output runs through your dashboard ammeter. Neither the present wiring or ammeter are up to handling 100amps. So, the first change would be bypassing the ammeter and running the 100 amp alternator output directly to the battery stud on the starter relay through a suitable fuse or fusible link. If you do some searching through this section of the forum you will find more on this change. When doing this many people change the ammeter over to a voltmeter.

I would sit down with a big piece of paper and draw out your new system after collecting the electrical requirements of all the pieces you want to add. Collecting the current requirements of all the new items will allow you to size the fuses and wire sizes properly. Also, to consider where to use relays like for the electric fuel pump and fans.

[Hop Head]

Yes, that's the plan is to switch the ammeter to a voltmeter.  My main concern is, is it safe to run a 100A alternator with the updated wiring without all the added components. I'm planning on a slowly adding the extra pieces when cash allows. So, I don't really know the requirements of the additional pieces yet. 

[Pete in NH]

I don't see any problem adding the 100 amp alternator now as long as you do the wiring changes to remove the ammeter from the circuit and upgrade the wire sizes and fuse protection fro the battery to the alternator. The alternator will only supply as much current as the car requires at any given moment.

I would try to collect as much information on the pieces you would add in the future as you can to get some idea of how to layout the new wiring. If you wait until later you will be always going back into the wiring harnesses to add one new thing at a time. You'll be making a lot of extra work for yourself and a lot of extra wear and tear on the harnesses.