Technical Alternator pains

Happy monday everyone.
Over the weekend I mounted an alternator from a 2005 Chrysler 300 on to my sbc. This alternator is 165 amps and im using it to replace the 60 amp gm alternator.
I talked to some of my Mopar buddys and they said "... just put a connector on one of the poles on the back, and if one pole doesnt charge the system switch it to the other pole."
So, I did. However the motor died no matter which pole I had it on when ever I pulled the negative cable off of the battery.
Can anyone help with what I might be doing wrong?

 

pulling the negative cable off the battery when the engine is running is one thing you're doing wrong....

Using an alternator that requires an external regulator, without the regulator, is another.

http://www.oreillyauto.com/site/c/d...=Search_01468_1430632_3090&pt=01468&ppt=C0330

 

Ok, so is there an external regulator that I can use?

 

That alternator is originally controlled by the PCM. Chryslers have done that for the last few decades. Your Mopar buddies are wrong. You don't just turn one on.
You would need an external regulator.

 

why do you need 165 amps?

 

Since I always use the GM internally regulated alternator introduced in 1974, and available in what I would feel are adequate amperages, plus it's near bulletproofness, makes me ask:

Why do you need 165 amps in a hot rod??

Cosmo

 

Why not just use a 12SI high output GM alternator?

 

http://www.dbelectrical.com/p-5313-chrome-chevy-alternator-110-amp-3-wire-setup-65-85-adr0336-c.aspx

Jack E/NJ

 

My friend said...........is the worst advice. From wiring guys, those are the three worst words.

 

I wanted to run a more powerful Alternator on my T as the 60a 1 wire I was using dropped to 12.5v at night with the lights and fan running.
I used a GM cs130 Alternator. Smaller case and around 100a.
Easy wire hookup and now the volts are at 13.5 with everything on...14.5v just after startup!
Lights are brighter too!
165 is welding amps!

 

Never. Ever. Disconnect the negative battery cable on an alternator supported electrical system. You likely fried all the diodes in the alternator and any sensitive electronics in the car from creating a huge voltage spike.

 

bigger/more is not always better - 165 is overkill x2, unless running tons of electrical stuff - go to www.powermasterperformance.com and then How To Choose A Hot Rod Alternator & other sites for info

 

The take the battery cable off was done in 1959 on a Mopar with a totally different alternator as a show and tell thing to prove that the alternator could supply power to the system. A lot of mouthbreathers still think that holds true in all cases.
I'm another one who says that there are far too many high output Delco alternators floating around that will bolt right on and hook up easily to screw with and try to hook up that particular alternator.
from the chrysler 300 board read post 2
http://www.300cforums.com/forums/ge...-trouble-shooting/152793-voltage-jumping.html

 

Go to your local U-Pull and vulture a Bosch internal regulated alternator off a BMW E36 [1990's 3 series]
They are rated at 90amps
If you can find one off a mid 90's BMW "luxo-barge" [5 or7 series] they go up to 180amp

Bosch is quite universal in fitment

 

Not too many of those in most bone yards that I have been and even then you run into the deal where if it craps out on the road you are frigging stuck. That odd ball crap might sound wonderful to some people but this guys needs a simple high output alternator that he can find a bolt on replacement for anywhere at a reasonable cost. That first BMW alternator might be cheap at pick a part but the replacement is 204 bucks at O'Reilly's and you have to wait for them to get one in most places and that just screwed his weekend road trip to a rod trot all the hell if it craps out.

 

True.

I run a 200A in my Falcon, but I have AC, heated seats, and about 1850W of amps in the trunk.

 

They must think those BMW pieces of crap are special in USA, down here they're "Bankruptcy on wheels".
When [not "if"] they eventually cook the engine, the whole car is not worth saving.
BMW's use Bosch, they same as Aussie Falcons down here.
The only thing that usually goes wrong with alternators is brushes , bearings, or the regulator.
Once those alternator is chosen [what people are reccomending on this thread] then it is easy to repair at a later date, or cannibalize another one from U-Pull

 

This is what you need to make it work. Note that the large output post is not shown on the alternator.

 

I have one ordered.

 

Both fans, water pump, air compressor and so on.

 

Got one ordered.

 

Thank you for your help

 

Way back when you could still buy a new Pinto, they had a MPG model. 1600 cc, manual trans, no air or power steering. Those cars had the big 90 amp alternator on them. Why???

Better fuel economy.

A 35 amp alternator would have been adequate. So why the 90 amp?

Driving at night with the headlamps or anything else turned on the 35 amp would have been working at around 75 percent capacity. The 90 amp.... Around 40 percent. The more draw... The harder it works and more horsepower robbed.

So a 135 amp alternator may be overkill for the demand... But look at all the trees he is saving by getting better mileage!!!



Sent from my LG-H343 using The H.A.M.B. mobile app

 

Is the smiley for sarcasm or do you really believe what you posted? There is no free lunch. The more current the alternator puts out, the more energy it requires from the engine. It will require the same amount of energy from the engine to put out 35 amps from either alternator.

Also, 75% of the 35 amp output would be 26.25 amps which would be 29.17 % of the 90 amp output.

 

746 watts equals one horsepower, or at 14 volts output, 54 amps at 100% electrical efficiency. Alternator or generator size has nothing to do with that. No electrical device is 100% efficient however, so actual horsepower required to generate a given output will be slightly higher. It will also depend on the rectifier design used to convert the AC voltage into DC; a full-wave unit will be more efficient compared to a half-wave type (and half-wave rectifiers are very rarely used). But generally speaking, any automotive-type alternator will be within a few percent of any other in terms of electrical efficiency, so the difference in power needed to generate any given output will be too small to measure for most.

Mechanical losses are another matter; pulley ratios, belt slip, bearing drag, and cooling fans will increase the power needed to generate output (easily doubling the power needed), but the advantage will almost always go to the smaller unit.

 

You're welcome, glad to help. Did you get it working?

 

Wow...... I will break out the slide rule next time.

Percentages are approximate. It has been over 30 years since a Ford engineer explained it in one of my classes. Point is, it takes less horsepower for a higher amp alternator to produce a given amount of amperage that the lower amp one would use.

Sent from my LG-H343 using The H.A.M.B. mobile app

 

It's like saying a larger displacement engine will use less fuel to move the same vehicle the same distance at the same speed than a smaller displacement engine will.

 

Either the "Ford Engineer" was wrong or you misunderstood him (or remember wrong 30 years on). The amount of drag created by the alternator for a given output is not going to vary by a measurable amount based on the potential ability of the alternator to produce higher amperage charge rate. In fact theoretically a higher output alternator is going to have stronger magnets and a heavier rotor would have a Higher drag than a smaller alternator. If 35 amps was all that was required to operate the electrical needs and charge the battery, it would require about .66 HP to do so, regardless of the Potential output available from the alternator. And if that 90 amp alternator were to operate at full capacity, it would still only take 1.7HP to turn. BUT, alternator amperage ratings are what the alternator is capable of producing at 6,000 RPM (the shaft speed, not engine RPM). This drops as RPM drops. A General rule of thumb is that at idle the output is going to be Less that have, more like 40%, of max output - so that little 35A alternator is only putting out about 14A at idle, and That is not enough to keep the battery charged, much less the lights shining. The 90A alternator is going to be producing about 36A at idle. To go along with this, the Pinto MPG had taller gearing, taller gearing means less RPM on the road, equaling Less out put from the alternator. See the cycle here? Their choice was to either go to larger alternators or bigger and heavier batteries. Remember that the alternator is only going to put out the amount of amps that are required by the demand of the system at any given point in time. Charging a discharged battery is usually a bigger horsepower drain than the rest of the electrical system!
Additionally the Pinto MPG model didn't come out until 1974 and it used the 2.3 SOHC motor, the 1.6L motor had been dropped in mid 1973.
The move to higher output alternators (Before high electrical demands) had to do with manufacturers running taller gearing meaning they needed higher charge rates at low RPM, along wanting to run smaller and lighter batteries, with the weight savings adding to increased MPG. They were looking to cut weight everywhere and the same time the Pinto's got the big Alt and small battery, they also got aluminum bumpers among other weight saving measures.

 

We got it mounted but didnt get the external voltage regulator till yesterday.
Going to give it a shot friday night.