Some considerations about the charging and wiring upgrade and your worries about

[Nacho-RT74]

Conect backwards the ammeter wires won't kill anything but just a reverse Charge and Discharge reading... that's all

[Nacho-RT74]

maybe a bump would help for ppl who was searching it

[crj1968]

 

[PocketThunder]

Nacho,
Can i wire up my car this way and remove the original black 12ga wire from the alternator to the bulk head on the engine side?

This will allow me to use that original opening for the new black 8ga wire. My bulk head only has one spare opening and i will use that for the red 10ga wire return to the starter relay.

thanks,
Paul

[Nacho-RT74]

The deal on diagram is not just use thicker wiring, but also bypass ( somehow ) the weak packard 54 terminals, unable to hold the high loads.

If you want to remove the stock existant wires, go ahead, but run a 8 gauge wire using still the packard terminals kills the main object on this keeping a weaker point, more than the wires itself

IN FACT, I called parallel just because if you want to keep the existant wires  being still in good conditions, and reinforce them with the parallel path, but being in good conditions or not, stock ones can be removed and just keep the bulkhead bypass path

[b5blue]

What I did using a sealed marine grommet. If needed it can be unscrewed to remove 8ga wire. 

[PocketThunder]

This is what I am asking. This still uses the original AMP gauge. The MAD electrical instructions tell me to discontinue the AMP gauge and keep all power on the engine side of the firewall. I would like to keep the AMP gauge for original purpose, but don't want to burn up my Charger. My black wire on the AMP gauge started to burn up last week when I was driving the car.

Paul

[Nacho-RT74]

What I did using a sealed marine grommet. If needed it can be unscrewed to remove 8ga wire. 

I'm soon to use this to be able to disconect the thick wires



One short end to splice into engine bay wiring, the other longer end to reach straight without splicing ( just  eyelet terminals ) the ammeter studs, keeping plug on engine bay side, and clean installation behind the dash.

Still undecided on use 8 or 10 gauge. 10 is really enough for our cars actually. The 8 gauge link I got is 2 foot, the 10 gauge is 4 foot. Couldn't find the 4 foot 8 gauge link.

Maybe if 2 foot is enough to reach ammeter from engine bay side, will keep 8... Or not LOL

[Nacho-RT74]

This is what I am asking. This still uses the original AMP gauge. The MAD electrical instructions tell me to discontinue the AMP gauge and keep all power on the engine side of the firewall. I would like to keep the AMP gauge for original purpose, but don't want to burn up my Charger. My black wire on the AMP gauge started to burn up last week when I was driving the car.

Paul

That's simply PERFECT! And actually is what MaMopar made on high fleet cars! Although they didn't remove tne wires on cab side to bulkhead, simply let them free into the engine side plugs but still into bulkhead cavities. But sure you can remove them and give some other use to those cavities for extra acc

[Nacho-RT74]

I guess began to burnt on firewall area ( plug or bulkhead ) which is the FIRTS point they begin to burnt out, due the packard terminal weakness

Did you upgrade your alternator ? Seriouslly think on that. Some alt able to feed 45 to 55 amps iddling will be great. That's the real reason why the terminals begin to burn! The low charge capacity iddling. You'll be saving your ammeter too with that, that's the next spot on the line if keeping stock capacity alt

[Nacho-RT74]

One Note about madelectrical statement... All power on engine bay isn't true... As far main splice is into the cab ( which is still the one feeding fuse box, ign switch, headlights and ammeter ), that will be the main power buss inside. Will need heavier modifications tu run it outside the cab

[PocketThunder]

Ok I have finished my re-wire. Here are some pictures to follow along at home. First one is me broke down on the interstate during rush hour. The black wire from the alternator started to melt and I lost power. It came back on after about 10 minutes and I drove it home 2 more miles.

PT

[PocketThunder]

The finished product on the inside and engine side of the bulk head, and my shopping list at the parts store.

[Nacho-RT74]

Does it look nice and is correctly done, althouht in your case what I had made is:

-Diff route than the bulkhead, just to be able to keep the engine harness easier to plug and unplug, hence I draw a grommet at a side of bulkhead in firewall

- use  terminals, bullet kind if you want, to link the fuse link to the red wire... Easier to replace in case of blown. Bullet terminals are able to hold the load way better than the packards


Thats just about preference

Now an advice... isolate the eyelet terminals "sleeves"  to ammeter. Shrinking tube is fine to do it... Dunno ir is late for that or not. I usually use dual tubes section/layers for extra safety.


And, don't forgett to upgrade/replace the alt with some alt able to feed between 45-55 iddling. Trust me that will be safer to all the charging system, opposite to the people thoughts. Dunno the size of the pulley you actually have on alt, but the smaller as posible will help on increase the charge capacity iddling. Your ammeter and all the car will be gratefull with that.

Be sure to tight correctly the ammeter studs

[CRW-FK5]

Very good read, Nacho.  The standard alternator in my '70 Charger (440) just went bad and I will need to replace it.  I am currently running the stock ammeter gauge and have had no issues (wires and connection points at bulkhead look very good).  I do have the typical headlight dimming at idle along with stereo cutting off when applying brakes at night (with headlights on), so I really want to do something about that. 

I do not know what amperage my current alternator is putting out but wondered what size I can safely use, before I upgrade to the parallel wire configuration, as I'll need to get the car back on the road first.  I realize there are risks no matter what when running stock ammeter, but is there a specific alternator that does produce more amperage at idle and still considered "safe" with the stock ammeter gauge, so I can at least reduce the headlight dimming for the time being?

Thanks.

[Vegas_Nick]

Nacho,
On my 74, I'm going with a one wire alternator from Mean Green. I am going away from the ammeter and will eliminate the pass through wiring going directly to the welded splice. Similar to the method spelled out here: http://www.madelectrical.com/electricaltech/amp-gauges2.shtml

Any idea of the total amperage load on that side of the car fed by the 16 gauge fusible link? I am planning on going with resettable marine grade circuit breakers for the battery to alternator connection and the battery to car connection. What I have seen looks like a 50 amp breaker to replace the 16 gauge fusible link.

[Pete in NH]

Hi Nick,

Those fusible links were not exactly precision devices when it came to what amount of current would melt them. 50 to 60 amps was about right so a 50 amp breaker would be fine.

[Vegas_Nick]

Hi Nick,

Those fusible links were not exactly precision devices when it came to what amount of current would melt them. 50 to 60 amps was about right so a 50 amp breaker would be fine.

No doubt! Way too many variables in that to make it precision. Cool, I will go spend a few dollars with West Marine!

[Nacho-RT74]

Sorry arrived late

The full load required is the load the battery will require to be recharged from totally discharged with a good alt. Too many variables out there.

Is dangerous to fit a thick fuse link because in case if short, this must be blown way before the short burnt with a bigger damage anything else.

The advantage of the fuse link is this is able to hold as small short around without burnt. IE an accidental positive wire you are handling and get touch againts some chassis point that you saved to keep there. Able to get you some sparks.

On stock system, Chrysler used 16 gauge wich with stock systems is fairly enough. On upgraded systems, 14 is way enough, and that's just because if you get way discharged a batt, this will hold better the recharging process. But ON NORMAL operating conditions, the 16 gauge works too and is also enough since will keep safer the full wiring because will burn sooner than the 14 fuse link. In fact, with an upgraded charging system TRUST ME the fuse link will get less load going throgh than the previous stock system. The fuse link will get what the ammeter is getting too. So if the ammeter is getting less load going through, the fuse link will be the same.

And well, bypass the ammeter and everything else you'll make is just right the opposite I stated on this thread LOL. But its at each own. I'm just telling how to keep safe your stock system if you want to

[pipeliner]

I just bought all new M&H factoring wiring for my 70 Charger. I went through this thread and somewhat understand it because I'm not very good with electronics. I plan on using maybe a 120 amp alternator, electric fans, vintage air, no ammeter, using Dakota Digitals and a killer stereo system. Nacho, how would you wire this car up to make everything safe with my wiring and what alternator and battery would you use? Thanks!

[Nacho-RT74]

This thread is about how to keep safe the stock system design. Since you are not using anymore the amm you can simply link both wires together on a junction an still run parallel wires like it is on diagram.

That will give you a power buss to the cab too, useful for the audio power plants.

Running a regular modern  stereos ( i.e. 50 watts x 4 or so ) an alt able to give around 45-50 amps iddling is still plenty enough. Now if you mention a killer stereo I guess you meant power plants subs and stuff like that? 60-65 IDDLING amps should be enough to feed fans and audio system, and one of those HUGE power capacitors for the subs power plant. That will keep safe the alt and the dimming it happens at every boom made LOL.

Without an ammeter, you can get the juice from batt, but i still think the alt stud is safer, since mostly of the juice will come from it while car is running ( while alt is able to do it )

The deal is usually manufacturers doesn't provide the power alts are able to give at iddle, unless they provide an output power chart/diagram.

You can also link the alt to the starter relay stud or straight to batt with a thick wire ( 10 or 8 ), and use just one wire to feed the internal junction made by the original amm leads ( from batt or starter relay ) for the added devices, throught the firewall, adding a reinforced batt power source to the cab. This instead the parallel wires on diagrams posted here.

[pipeliner]

Ok, Thanks!

[Nacho-RT74]

as an update, cheking 74 FSM diagram, IT SEEMS with 65 amps alt, the wiring runs like this on them:

I simply removed the red wire between bulkhead and starter relay because diagram is not clear enough about if should stay or not with 65 amps alt. I find not logic to run 2 parallel fuse links because will take way long to burn, and damage could be bigger. There is also lot of added info when running trailer tow package on diagram

NOTE I TALKED ABOUT THAT EARLIER, EVEN MY INITIAL DIAGRAMS SHOWS DUAL FUSE LINKS ON RED LINES... not good really...part of the learning process

I can't find really a reason for the 16 gauge fuse link between black 8 gauge wire splice and bulkhead, because even if it blows, the line remains hot from the grommet side, but is what diagram shows.

however, this will work too as an upgrade

EDITING:
SORRY!!!! THERE WAS A DIAGRAM HERE THAT I REMOVED ACCIDENTALLY. I KNOW HAVE SAVED SOMEWHERE BUT CAN'T FIND IT.... WILL UPLOAD BACK WHEN IF IND IT.


EDITING 2... FOUND THE DIAGRAM I ACCIDENTALLY DELETED

[Nacho-RT74]

I'm going to post a new diagram about I will definitelly make on my car once reassembled... 10 gauge wire and the "trailer plug loop" wire with the quick disconect plug I shown earlier. Pretty sure will remove the stock red wire from forward light harness ( the original getting the original fuse link ) for easier and cleaner job, no extra splices and just using one 14 gauge fuse link.

Once you get a nice alt, the red wire feeding the fuse link from amm will be enough on 10 gauge really because barelly will get high loads.

I keep the stock black 12 wire to be able to feed the main splice from both sides... just like doubling the paths

[Chargerfreak]

Hi.

Because im from The Netherlands we use metric system.

Im making the bypass with 4mm2 wire, which is about 11 gauge.
You seem to advice thicker wire, why when the system would run on only original wiring too?


I'm using the original system of alt to batt, AND run the bypass.

Chris.