They are basically all the same Delco unit for GM cars during that era. There is not likely a need for a higher rated one than stock.
Actually, there is very good reason to use a larger unit. With the advent of stereos exceeding 500W per channel, aftermarket lighting, nav systems and whatnot, not to consider the situation with older systems deteriorating larger alternators are a good idea. If you want to go with the factory 10DN unit, ask for one clocked correctly foa a vehicle "loaded." I think these went to 80 amps. The aftermarket is loaded with extra output units but I would do the conversion to the 12SI units, rated up to 120 amps. Food for thought. Ray
Familiar with that but Lord I hope no one would cut up a GS for such a reason. Much of the load is taken up by the battery. That is why an electrical system with a regular alt can handle a system with a seemingly high rating. Now if you want your system to involuntarily entertain your neighbors with your bass from a block away perhaps something new might be needed. Incidently, noise induced hearing loss is the most common occupational problem in terms of numbers in the US. I have handled many sad cases where speech impairment has ensued as degraded hearing moves down into the speech frequencies. Just ask Robert Plant. Call your next case.
Huh? Actually, I hear you. The only fly in the ointment here though is the use of the vehicle on short trips. A high output alternator will charge a battery quickly, especially if the unit has sat for a while. Lower output alternators must overcome the battery's internal resistance, which can be substantial if discharged beyond halfway. In that case, a trickle charge would awaken the battery, allowing the alternator to take over without damage. Note; the high output alternator takes the load off of the battery when high loads exist. Pulling the current from the battery will tax a low output alternator, eventually burning it out from excessive heat. Hopefully, the bass emanating from these kids' stereos precludes them from driving a Buick. That would truly be a travesty, although the sound deadening in a Buick might allow the use of less power. Besides, their POS's need the cover of stereo power anyway, the engines don't make any. Ray
Here is what I did. And I'm pretty darn pleased with it. Read on... http://www.v8buick.com/showthread.php?s=&threadid=44117
Ray, Keep in mind that virtually every alternator will have the same charging rate, except in the rare circumstance where you are pulling HUGE amounts of juice. This is because the voltage regulator will still hold you at 14 volts or so, and adjust the duty cycle accordingly. If an alternator is pumping away at a 100% duty cycle, then a bigger alternator will charge the battery faster (since the alternator has essentially become a current source instead of a voltage source). However, in just about every real-world situation, an alternator never runs at 100% duty cycle (as long as the car is moving). If the car is idling, then even a high-amp alternator is still spinning so slowly that it won't maintain a good charging voltage. Agreed about the young kids and their stereos By the way, this is a good place to give a plug for a vendor who does a super job- everyone should take a look at www.madelectrical.com - especially the tech section. Very high quality stuff at pretty decent prices. -Bob Cunningham
i just recently did a CS 105 amp one wire conversion i paid 20 bux for the alt came out of a mid 90's buick front driver and 20.60 for the conversion plug from M&H electrical fab. it now has more than enough power for what i need @ www.wiringharness.com Rich Martel 70 GS 455 BPG #1599
Bob, You are partially correct regarding the charging at wide-open. Something to consider, however, is that the high output units better support the additional loads of stereos, lighting, etc, which is availabel now and not 30 years ago. The idea is to have the alternator supply all of the current necessary when it is being used. BTW, when I rebuild my 12 SI for the additional 15 amps to 100 amps, I noticed that the alternator now completely supports the load the A/C puts on the electrical system at idle, where before, the volt meter dropped slightly at idle. It now stays at 15 volts with the A/C on and the blower on high, at idle speeds as low as 500 rpm. It dropped to 13 volts at 500 rpm before. On start up, especially when taking short trips, the altyernator will run at close to 60% of rated output right after a start-up. This depends on how quickly the engine starts, and the condition of the battery at start up. The addition of stereo equipment, electric fans (which typically run after the engine is shut down) will discharge the battery slightly, adding to the load the alt sees. In short, the electrical options have changed drastically over the last 30-40 years. If we want to have these niceties, it is necessary to pay the piper. Adding these loads without using the correct alternator will shorten the life of a lower putput unit, and reduce operating voltages, shortening the life of the new components as well. Doing it right is always cheaper than doing it over. There is a very good reason alternator outputs have doubled or even tripled in the last 30 years. Output adds load, directly affecting emissions and they add heat to an already crammed engine compartment. They wouldn't use them unless they were necessary Ray
