New Alternator Wiring Upgrade Configuration

[Blacky]

I did mine last weekend using 2 gauge wire as 4 gauge was not available locally. It looks and works great. Thanks for the idea and How To.

[svxcess]

Originally Posted by SSSVX

Your alternator is rated at 160A.
But at idle, how many amps would it produce? Do you also have
the info of how many amps does a stock SVX need of its entire electrical system?

The stock alternator produces up to 95 amps at 3300 rpm
Output at idle: up to 34 amps at 750 rpm (which is 35% of maximum output)

High-Amp rebuild produces up to 160 amps at 1600 rpm
Output at idle: up to 88 amps at 750 rpm (which is 55% of maximum)

Up to means that it is capable of putting this current out, but doesn't unless the demand is there. The current draw swill be the same no matter what aalternator you are using, although the high-amp unit is more efficient.

I don't know what current draw on the stock electrical system is as it depends on what accessories you are using. Maybe someone here has these figures.

On a nice summer day with the sunroof open, all you may be using is your radio and whatever your engine requires. However, n a cold winter night, you use a LOT more: headlights, climate control defrost, rear defroster, heated mirrors, etc.

Idling at times like this, the car's electrical loads may exceed the low-speed current (amperage) output of the alternator and when this happens the shortfall comes from the battery. This will result in a drop in the electrical system voltage as the battery delivers the additional electrical current to meet the demand. This is equivalent to the brown-outs experienced by homes and businesses when the electrical demand is more than the supply. This is where the benefits of high-output alternators come in.

I just like that the alternator doesn't have to work so hard to provide the necessary power

.

[benebob]

What's not to like is:

1. Upgrading an alt is like putting a bandaid on a zit. You're only hiding the reasons for needing more power. Higher resistance due to corrosion, poor grounds, age of wiring etc. Only real need for an upgrade alt is if you're running more power accessories then were stock. If you read anything about upgraded alternators and I posted in it you'll understand this more. Esp going from a 95 to 160 amp alt but that is another story.
2. John wasn't fully explaining exactly what he did which can lead your average 18 year old non electrician to follow his proceedure partially or even completely in their mind and be left with a very large fire hazzard. Which is something none of us here would want. If you look at my initial post I stated "I think what you did was okay" but I also had quite a few concerns reading through his master plan as the details weren't there!
3. I'm not convinced at his wiring of the two smaller 10 gauge wires which control the ignition switch and dash stuff if I remember right as my FSM is elsewhere directly to the battery. My educated guess without the diagrams is that these are from the alternator simply so that should a short occur when the car is sitting that power isn't going to be drawn from the battery and kill the battery while heating up the wiring due to the draw hence risking fire. Like I said I don't have my FSMs at the moment but I'm fairly certain that is why modern cars are designed that way!

Knowing John I'm sure he has researched extensively more than most would here. He is one of the few people who is more anal about their car care then I am (believe me I take pride in anality so in my mind I'm complementing him by suggesting he's anal!). I just want these things explained further so that the average current SVX owner understands what it is they are doing and the risks involved if it isn't done right. Also, knowing John he's the first one to admit that he's probably not necessarily the right one to be explaining it either but I was hoping his support team would answer the concerns that I have and that I'm guessing Bill is also mirroring.

Think about it this way, how many hoods have you opened and seen melted connectors on the alternator and around the battery itself. I'd say after 10 years a solid 1/2 of the cars on the road have had someone playing with the wiring that probably shouldn't have which led to the meltdowns. Sure most of these cars are still on the road BUT the risk is still there!

Originally Posted by processengr

Hi !
I'm not clear on this...

• He up-sized the source from 95A to 160A .
• Removed all wires from the output of the 95A source
• Ran a up sized conduit (4ga) rated at 160A to a fuse (80A) through an area than would not be impinged upon in the event of a accident.
• Attached the wires that were previously attached to the 95A output alternator to the downstream 80A fuse...Whats not to like?

[svxcess]

Ben,

Thanks as always for you input and concern. I don't know the best way to explain this mod clearly so that your "average 18 year old non-electrician could follow follow this procedure completely in their mind or else be left with a very large fire hazzard." For these types, the basic "original" alternator wiring mod may be sufficient.

I am attaching the complete Power supply routing diagram from the FSM. The two wires circled in green are the ones I removed. It seems that one of these wires controls the headlight relays through the ignition switch to allow the headlights to come on when the ignition is on and go off when the key is out.

Remember that one of those smaller 10ga wires that was replaced was the original charging wire back to the battery. I just replaced it with one for better current flow and less resistance = less heat = more current/ voltage.

My old ones did not look that good after 12 years. I could have cut them all back and replace them with newer ones of the same gauge, attaching them at the original points.

Please look it over and tell me what you see of concern.




Have to go to work now. I think I may have a touch of "Anal Glacoma"...

I just can't see my a** going to work on such a nice day

.

[svxcess]

Originally Posted by Blacky

I did mine last weekend using 2 gauge wire as 4 gauge was not available locally. It looks and works great. Thanks for the idea and How To.

As far as wire gauge goes, all high-amp alternator shops recommend 4 gauge wire upgrades to the charging system when installing these units.

This covers them as they do not know how your system is configured. High power stereo amps, subwoofers, etc. eat a lot of power and could easily use most of the output and create heat and other problems.

Maniac Motors (where my alternator was built) told me that if I was using their alternator on my stock system, 6 gauge wire would be more than sufficient, but it is not easy finding that gauge, so i went with 4 gauge.

.

[newsvx]

Hey John,
First, the installation that you and OT did looks really good! Really pretty!!

That said, I don't see the purpose behind the mod. If, as I understand from your first post, the mod was done because the original wirinf was all corroded, etc, then why didn't you just replace the original wiring and clean the connections. I am a firm believer that the auto engineers "knew what they were doing" in their design of the electrical system, as with the rest of the car. Of course, as most of you know, I am inclined to leave things as stock as possible (although I do have aftermarket wheel on the '97 - the '92 is another question all together ).

As a point of reference, I have never noticed my heater / AC fan motor losing speed at idle - but then again, I may not have been paying close enough attention. Or maybe my terminals are clean .....

But your installation sure looks nice!!

Harry

[Trevor]

Originally Posted by Trevor

I did not suggest that you have removed the fusible link, but you have bypassed it in respect of the alternator sub wiring. You state in your original post:-

“I removed the two white wires and cut them back about two feet. One of these wires was factory-spliced into three wires close to the battery. I put new ring connectors on each of these wires and connected them straight to the battery.”

The original arrangement protected these circuits as they were subsequent circuit wise, to the fusible link. You did not answer my e-mail query, as to whether your faulty wiring was in fact original. If not this could have lead you astray with the rewiring and the desired connection via the fuse box and fusible link.

The heavy wiring you have correctly protected with a fuse and in respect of gauge should be OK. It is not at all likely that the heavy wiring could become overloaded to any dangerous extent due to the short length involved, possible voltage drop being the main concern.

Forget the sales blurb regarding oxygen free copper, however fine stranding providing good flexibility is worthwhile, as are good connections and mechanical robustness. In this regard you are much commended.

My previous post as per above, appears to have been buried. Furthermore at this point in the thread, I note that some incorrect statements have been made.

[TomsSVX]

Trevor, I was one of people who John had spoken with about this mod. I found it to be relatively simple and straight forward. I did not think it was bypassing anything at all simply relocation. I could be wrong but I do not see how this would bypass the fusible link as long as I understand John's plans

Tom

[Trevor]

Originally Posted by TomsSVX

Trevor, I was one of people who John had spoken with about this mod. I found it to be relatively simple and straight forward. I did not think it was bypassing anything at all simply relocation. I could be wrong but I do not see how this would bypass the fusible link as long as I understand John's plans

Tom

Tom,

Please refer to the Subaru Manual wiring diagram. The circuitry is arranged so that all circuits to the alternator are protected by the fuse link. Any direct connection to the battery bypasses the fuse link.

In respect of the direct heavy charging lead, this has been correctly protected by means of an extra in line fuse. It is the secondary control wiring which is at fault.

Cheers, Trevor.

[TomsSVX]

Originally Posted by Trevor

Tom,

Please refer to the Subaru Manual wiring diagram. The circuitry is arranged so that all circuits to the alternator are protected by the fuse link. Any direct connection to the battery bypasses the fuse link.

In respect of the direct heavy charging lead, this has been correctly protected by means of an extra in line fuse. It is the secondary control wiring which is at fault.

Cheers, Trevor.

I have not looked at them. Will take a look.

Tom

[Trevor]

Originally Posted by svxcess

Ben,

I am attaching the complete Power supply routing diagram from the FSM. The two wires circled in green are the ones I removed. It seems that one of these wires controls the headlight relays through the ignition switch to allow the headlights to come on when the ignition is on and go off when the key is out.

.

I regret to be a nark, but have to inform you that you are completely off track in your reading of the official wiring diagram. I think you may be confused with the crossing of wires as drawn. Only lines with a dot at any intersection or crossing, indicate a connection. I have never used this method, preferring to draw any crossing as a bridge over the crossed wire.

The headlight circuit is connected directly to the battery side of the fuse board bus, so that in the event of the fuse link opening, (Through over current, corrosion, or whatever.) the lighting will not be lost and a dangerous situation develop. The lighting circuit is protected further down the line, by inividual fuses for each leg, again as a safety measure.

[Francis]

wow beautiful. looks really great, i ll have to buy i high amp alternator soon i want to put heavy sound system in mine , im keeping an eye on this thread. thanks for doing it gives us ideas

[Trevor]

Originally Posted by TomsSVX

I have not looked at them. Will take a look.

Tom

Tom,

Yes have a look, the set up is b--- awful. Voltage sensing is combined with other circuits and the only protection for same is the fuse link. Surely a separate sensing conductor should be provided, protected by a properly rated fuse and supplied from the battery side of the positive bus bar. This could well form part of any upgrade.

Trevor.

[Nomad]

Question : Would it help if i have an underdrive pulley ? Since i have a very good sound system ( 2000 watts , 2 amps , 2 x 12'', ect... ) and i need to charge the battery every 3 days ?

Is that alternator could be ship to Canada ? the cost ?

Thanx guys !

[svxcess]

Information on the alternator can be found HERE


Also check out THIS THREAD on the high-output alternator. Price, comparisons to stock units, a little tech-read called "Alternator 101", etc.

Call Christian at Maniac Electric Motors at 972-557-5769 to find out about shipping costs to Canada. They are located in Dallas, TX.

These alternators are built upon request as needed. I have talked with her extensively and she is extremely knowledgable about alternators. Call her, tell her what you have for your audio system and about the charging issue and listen to what she has to say. I have talked with her extensively and she has never let me down. A truly great company to deal with!

An underdrive pulley would be unnecessary with this alternator. Something of a quick fix for our stock alternators, but not without problems of their own

.