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MAD Elecrical Ammeter Bypass VS Parallel Charging Wiring

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I have been reading alot of postings on other sites discussing which charging system upgrade is best for our Mopars. The MAD ammeter bypass has been recommended on this site by some but parallel chariging wiring is recommended on other sites. I am curious and would like to know if any of you are familiar with both upgrades and if so, which one are you using and why do you prefer the one you chose?
 
I'm just in the beginning of my wireing and am doing a hybrid of the both systems... My one wire powermaster alternator instructions say to run a 8 ga wire to the battery and hook everything else up as usual... I like the mad electrical ideas of relays on the lights and nacho from b body's only' s idea of relays on heater and accessories as well and the feed from the alternator side... so I plan to run a 4gauge wire from the alternator to the battery and 2 8 gauge wires to the bulk head and to the accessories from the post on the alternator... I want to run wire than to the starter solenoid... I plan to use 4gauge ground strap from head to fire wall to a stud and from the transmission to the body and from there another ground to the trunk. Taking from my boat experiences the car will ground if it was glass... the switches will activate the relays from the original style harness I will duplicate in a larger gauge wire.... the fuseable links will be as recommended by mad and nacho I'm less familiar with the parallel system and have questions about the old wires to the voltage regulator and the wires behind the alternator... '67 coronet sedan 318 points. I am also bypassing the ampmeter for a volt gauge...
 
although I'm the author of the parallel wiring diagrams and thread, is not actually MY idea, but just a modification of how MaMopar wired high equipped cars with big alts.

On these cars, the wires going from batt and alt ( 8 and 10 gauges instead our 12 gauge stock ones ) taped with engine bay harnesses doesn't reach the bulhead, and actually got a separated high load terminals to run though the firewall with a grommet at a side of the bulkhead

I call it parallel just because stock ones running allong the engine and forward lighting harness from alt and batt are still in working order, doesn't beed to be removed, just reinforce with the extras ones I talk about throught bulkhead. Mostly sure if stock ones got some damage usually are easy to service and still keep them working and still run the parallel path.

What I have to say about this:

1- the first you need to know is... LEARN about what it means the ammeter reading ( which IS NOT an alt gauge, actually a batt gauge ) once you learn what this reading means, mostly sure everybody will undertand this gauge doesn't need to be removed. My personal example... I'm running a 100 amps Mopar gauge ( or it was what Mopar box said about this alt ) with stock 40 amps gauge and my ammeter is completelly safe with no high loads going through, so no heat there anymore....

2-MADelectrical page even is really helpfull got some WRONG afirmations there. On their mod they state the main splice is being moved to outside the car wich is somehow wrong. The main source splice will be ALLWAYS inside the car, shared by the ign switch and the welded splice where everything is sourced, between alt and ammeter inside the cab. There is no way to change that unless a heavier mod on harness. Which they are making is converting the starter relay stud on a bigger Junction that actually was between alt, batt and cab, but the sources splice is still on same spot inside the cab, like previouslly was.

What their method helps is share the cab sources paths by two wires, already existant on our cars ( removing the weakness of stock terminals ), but without care where comes the power, alt or batt. Since won't care where it comes the power, then the ammeter is being removed and replaced by a voltmeter....

Nothing really wrong with this, but simply is not required if you are restoring ( do we really know what restore a car does it means ? keep yoru car in working order like factory did ? ). Is just about prefference. Myself, preffers the ammeter


3-Fuse links... they are able to hold small or momentary high loads so won't blown with any small accidental short like any regular fuse will do ( our cars already got fuses for that ), but still will keep safe your car on a big event on main parts of wiring. That's why I like fuse links ( and I guess same reason for MADelectrical crew ), and makes an easy installation being part of the harness itself, without any extra device added. Latelly somebody have talked about maxifuses... that is actually also a regular fuse, what will blown at the stated rate, without a chance to hold a small peak


4- On my thread about the parallel wiring, I have learnt step by step all allong the process, and even initially I post to use two fuse links, one for each wire between ammeter and batt, actually I made a correction at the end, advicing is way safer and better to use JUST ONE fuse link, so splice both wires ( parallel and stock ) into a heavier gauge fuse link. Dual fuse link there will take way longer before blown, so more time to bigger damages.

MADelectrical shows to install two fuse link, one coming from alt and one running to cab. Myself I don't consider necesary that. On stock system if there is a big short, the only source able to hold the short sourced is the batt never the alt, so why a fuse link running to alt? on a big short the engine will stall &/or the voltage regulator power will be cut, and the alt source stops

- - - Updated - - -

sleepar, if you link alt and batt together, and even more, removes ammeter, won't matter anymore where your source any extra device, batt, alt or whatever junction around, so don't make an unecesary wiring job to take extra sources. Simply use a junction or buss bar for everything, Or get the power from the closer point available, per you needs. You can use the starter relay as a main Junction if you want.

The reason to source all the accesories EXPLICITY from alt side is just when ammeter is still present, to keep the correct reading and don't need to add stress on ammeter and related wiring.

With ammeters, if you source any added device from batt side, the power coming from alt will go through ammeter and bulkhead to source THIS devices like if batt was sucking power ( then a constant discharge reading, constant load there, heat ), where ammeter doesn't need to read this if alt is able to source everything from the right side of wiring
 
Would there be a predictable adverse effect with a trunk mounted battery? If I'm not concerned with originallity could an in-line fuse be used where you are using fuse links? I have a 120 amp 3 wire alternator by the way. Thanks Nacho for your in-depth study of this subject!
 
The problem with using fuses in place of the fusible link is not the fuse...it is the fuse HOLDER. The max fuse idea in particular is a new problem waiting to happen; the holders' terminals are typically cheaper than than the stock firewall connectors that corrode, so these max fuses solutions will very often corrode and not last long. They are good for troubleshooting a short in the system, but I tell people to never leave them in.

Fusible links USUALLY have much better terminations and only 2 total terminations as opposed to a total of 4 terminations in a fuse holder setup (2 of which are often very poor, as explained above).

The other issue with big inline fuses is if they will blow with just a simple transient short as mentioned. To avoid that, you use a slow blow (time-delay) fuse. But then you have to balance the fuse rating so it will blow fast with a hard short but not with an intermediate level of current draw over many minutes. Fusible links have been (kinda) figured out to the best compromise level for those factors.

One other new twist showed up on a forabodiesonly discussion just a few days ago; someone ran a wire direct from the alternator output to the battery and ended up with repetative surge (flicker) in the system voltage in mid-RPM's. Another fellow provided the answer: not tieing the voltage regulator's voltage input to the battery too caused the VR to see a different voltage that than at the battery due to the car's harness voltage drop; that caused the 'flicker' in the regulated voltage.

So whatever you do, the VR power feed needs a good, low resistance path to the point where the alternaotr output ties into the system.

http://www.forabodiesonly.com/mopar/showthread.php?t=283992
 
Would there be a predictable adverse effect with a trunk mounted battery? If I'm not concerned with originallity could an in-line fuse be used where you are using fuse links? I have a 120 amp 3 wire alternator by the way. Thanks Nacho for your in-depth study of this subject!

Also, would I still need the extra heavy gauge wire (8, 6, or 4 awg) from alternator to the starter relay with a 120 amp alternator ( as recommended by alternator manufactorer) or will this wiring set-up negate the need for anymore than the two wires from alternator listed in the parallel diagram? Again, this is with a trunk mounted battery.
 
actually the fuse holder AND FUSE ITSELF... I'm not in favor of fuses on main system. Is not uncommon to get some higher amperage spikes on charging system able to blown a fuse, but never a link

battery on trunk... same conditions on everything, just heavier gauge wires to save resistence added due the lenght
 
If I was to keep the amp gauge I would solder the contact.... I understand the mix better now ... My 4gauge wire from the alt to the battery and eliminating the amp gauge allows me to draw my power from the battery terminal making it the bus bar... and the grounds up grade to 4gauge will complete the circuit.... I will run the wires together into the cab to the splice and from there to the accessories each relay the original harness will stay in place except for the bulkhead connectors all those connectors will be a solid wire with some slack for service... no original contact will be used... I don't think I need to use the start relay as a buss because it happens at the batt terminal.... the wires for the amp gauge get connected with the addition of another 8 gauge wire from bat to supply the relays.... I want to put the relays under the battery tray for the lights rather than under the dash to them... the wiper motor will be on relays also so the only original harness willpower the park, turn and brake lights..... every other switch will be actuator for relay... I want to run everything at once with plenty of extra capacity in the wire... so I feel confident that the studies on this will gain me a solid wire harness. Every device gets it own relay and power wire and fuse.... I plan to use a bar fuse 200amp on the battery and no fuse link because I can't find a link to a 8 gauge roll of link wire is why they have 2 14ga link wire instead of one... if the wire pops the 200 amp fuse it will keep the battery from exploding and it's wire will all be toast anyways..... I do understand the fuse link and what it does and the inline fuse holders and they are cheap... thank you all for any input on this...
 
actually the fuse holder AND FUSE ITSELF... I'm not in favor of fuses on main system. Is not uncommon to get some higher amperage spikes on charging system able to blown a fuse, but never a link

battery on trunk... same conditions on everything, just heavier gauge wires to save resistence added due the lenght

OK. What do I do about the alternator manufactorer's recommendation of adding another wire ( 8, 6, or 4 awg) from alternator to starter relay stud? This combined with the parallel wiring from alternator will be 3 wires from alternator stud.
 
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Here is what I did on my 63. At the firewall bulkhead the 2 hot wires of one from the alt output and the other is the hot feed from the battery both bolt to the terminal sticking thru the firewall. They bolt up with a 5/16 head bolt. I jumped across that with a 10 gauge wire to bypass my ammeter as I bolted on the jumper wire at the firewall terminals. Then I added a voltmeter to moniter my charging system since the ammeter wont work any more and you can hook the voltmeter to a key on 12 volt source. In the trunk you can see in this pic the smaller 10 gauge red wire as thats my hot feed to the cars main power source as it goes thru the cutout switch to kill everything when the rod is pushed as the track says you need it with a trunk mounted battery. But coming off the battery cable I have a fuse holder bolted to the pos battery cable on the battery that takes a 70 amp fuse and feeds the smaller 10 gauge red wire as power goes thru the fuse that takes the place of the stock fuseable link and that red wire goes up thru the car to the starter relay on the firewall and feeds everything in the car. This has been working good for me since I put the car on the road in 2006. Ron

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Either way works, and I have both. On my '71 Charger, I just did the parallel wiring because it is super easy, just one wire from the Denso 136 Amp alternator to the battery (with a fuseable link), and leave the original connected too. This also makes sure the voltage regulator is seeing the alternator output. Note this system uses the original voltage regulator.
My '69 Coronet has a 144 Amp Single wire alternator. The alternator output goes to a mini-ANL distribution fuse block, and from the fuseblock to the battery (100 Amp fuse), and other accessories. The ANL type fuses are alot like a fuseable link, depending on the size they can take a several seconds or minutes of overload before it blows. A 100 Amp ANL fuse will handle 200 AMPs for about 20 seconds before it blows.
Both power wires from the bulkhead (each side of the ammeter) are connected to the distribution fuse block with a 50-Amp fuse. (not much to power under the dash).
I chained together another distribution ANL fuse block (4-fuses to a block) so I have seven fused output circuits, and the one fused to the battery. The starter is still powered directly from the battery, no fuse (don't want the voltage drop.) I wired the headlights to power off of relays that get power from the fuse block, same for the cooling fans, EFI, CD ignition, and stereo amplifier.
 
OK. What do I do about the alternator manufactorer's recommendation of adding another wire ( 8, 6, or 4 awg) from alternator to starter relay stud? This combined with the parallel wiring from alternator will be 3 wires from alternator stud.

just fine if you don't care ammeter. Not every car got ammeters ( chevies didn't, and lates fords either while Chrysler still had. )

guys, once again... the parallel wiring deal is to keep ammeter on the line... any other parallel path running straight to starter relay stud or battery, ends being also an ammeter bypass.

works? somehow yes, no like you think, but save some problems

If you are installing a more powerfull alt, able to hold the car load demand at the less RPMs as posible, ( or even at iddle ) you are really SAFER that you think!, not even needing the wire straight to batt, trust me!!!

the BIGGER problem on our cars, more than wires itself is the low output alts, making the batt source everything when alt is not able, and when revving up, the batt demanding all the power lost ( which is a HUGHE load sucker... THIS is the main problem!!! THIS is what makes the weak wiring spots even WEAKER! and dangerous

- - - Updated - - -

need to not THIS PARALLEL WIRING UP TO AMMETER, doesn't works ( and is not even needed ) with shunt kind ammeters... which as far I know began to be used in between 75/76. This cars as far I recall already got a bypass on firewall to feed the cab/main splice, beside the ammeters are not anymore full load, but a remote load sensor
 
I will say another reason I bypassed the ammeter in my 63 was I figure its over 50 years old and all of the current going back to the battery goes thru it. So I was wanting to not worry about my 50 year old ammeter going bad and leaving me stranded as I really dont want to have to crawl under my dash on the road with me on disability and the rollbar in my 63. I also did it because I put my battery in the trunk and decided to just do that also as it was more of a preventive maintnance move. Ron
 
How common of a problem is the surging voltage because the regulator is not sensing correctly after doing one of these conversions? I have made up my mind of doing the MAD conversion on my RR this winter and have just recently heard of this little glitch. My car has the 69 style regulator, but with electronic internals. Will I still have the pulsations?
 
How common of a problem is the surging voltage because the regulator is not sensing correctly after doing one of these conversions? I have made up my mind of doing the MAD conversion on my RR this winter and have just recently heard of this little glitch. My car has the 69 style regulator, but with electronic internals. Will I still have the pulsations?



You should not. I just use the standard Mopar electronic regulator for the 2 field alt and have no pulsing at all. Ron
 
I have been reading alot of postings on other sites discussing which charging system upgrade is best for our Mopars. The MAD ammeter bypass has been recommended on this site by some but parallel chariging wiring is recommended on other sites. I am curious and would like to know if any of you are familiar with both upgrades and if so, which one are you using and why do you prefer the one you chose?
How does parallell wiring work?
 
I wouldn't think that bypassing the ammeter would cause a surging problem. Basically the ammeter just passes the voltage through it. I bypassed my ammeter and also installed a headlight relay and don't have any problem with surging on my 63.
 
How does parallell wiring work?

It involves some additonal properly gauged wiring paralllel to the factory charging wires and is installed through the firewall but not the bulkhead connector and these additonal wires will splice into the factory charging circuit in strategically placed area's and will still utilize the factory ammeter. The additonal wiring will take the majority of the load off the factory wiring thus allowing you to still use the ammeter to monitor what is happening within your charging system. Nacho is well educated and experienced on this subject and if you google "Mopar parallel wiring" you will find his many post that are very informative.
 
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