Checkout this link, it helped me out big time to go OEM. When I took the car to Autozone,Oreilly's, and Advance Auto with the OEM setup, the alternator readings under 2000 rpms was 12.8v-12.5v at the battery sometimes 12.3v. But when you up the rpms to 2000 plus 13-15...... The guys at the autoparts store where stumped and tried to say it should read 13-15 all the time at the battery it was jumping around too much. These mechanics locally here wanted me to run a straight line from the +power of the alternator straight to the battery bypassing the Horn relay and Ext. Voltage regulator. In theroy it worked, readings at the battery were always 13-15. I bought 1 alternators and swapped it 3 times,2 voltage regulators, 3 different diagnostic test at $20 a pop from 3 different mechanic shops, 1 battery at $89 later......Come to find out it is the way GM setup the 7ft to 10ft of wiring so it would not fry the battery. The 14.4v is actually at the splice on the Horn Relay. Make a long story short. I ended up pulling that shade tree mechanic crap off and went back OEM from the diagram and 4 months later, no problems. Moral to the story like an old guy told me stick with OEM and you should not have problems, too many mods too many problems. Thats why its best to ask the old guys who worked on these cars when they were around, they will spend 1 hr talking about the 68 or 66 chevelle they had and the 13's and 11's they use to run and 10 minutes fixing the problem with a cigarete hanging from their mouth with a 2 inch ash hanging (that you hope they don't drop on your chrome valve cover or freshly painted motor but they never drop the ash)but they have a wealth of knowledge. I wouldn't trade their info for nothing and they are cheap too. Sometimes they will fix it for free or a case of beer or cigaretes to just beause they love these cars.:thumbsup:

here is the link: http://www.madelectrical.com/electricaltech/chevymain1.shtml

So, the "old farts" with the slide-rules actually knew something..... who'da thunk it!!:thumbsup:

I continually ponder why (especially after looking at all the "My xxx123 doesn't work...HELP!" posts) people continue to try and re-invent the wheel around here.... or throw hundreds of dollars at new entire wiring harnesses (hoping it'll magically solve problems because its "new") when some basic troubleshooting & repair will fix most issues...

(Great Post BTW - saved the link in my "Oh yeah read about that" file!)

Thanks for the link. This is awesome info. After reading this, I am gonna rewire a few things for better performance.

Thanks, I try to keep it OEM. I replaced some wires, but the setup is OEM. So if I have to trouble shoot, I can look at the diagram, grab the voltameter tester and get to testing. I had a 67 Caddy deville convertible where they rigged up a bunch of crap. It was like hell trying to find electrical problems. It can cost a lot to find the problems with the miles of extra and wrong wiring setups.

Those low meter readings at idle from a low output alternator sounds pretty "normal" for those old alternators, especially if your RPM's are on the low side at idle.

Some things were done because they were "cheap" to do as a solution, not because it was the best way to do it.

Give me a new wiring harness with modern insulation, a high output at low RPM alternator, and electrical upgrades any day. I love the styling on these cars, but there's plenty that can be improved upon...starting with electronic ignition.

And when you add on additional demands that were never available on these cars, such as electric fans or high end stereos, and/or heated powered seats, high demand A/C and more, you really can't go original wiring.

The look of original is fine if that's what you want and all you need, but I hope that doesn't stop guys with dangerous rats nests with cracking insulation from doing the right thing.

Steve

There is no good substitute for good electrical (or any other type) of engineering. Yes, those old guys with slide rules did know their stuff.
There are a lot of people (including on this forum) who have experienced something that worked for them and will swear by it. Things like one wire alternators, short cuts on grounding or adding interior lights, just to name a few. None of these techniques are so bad that they will not work. Sometimes they work sometimes they don't and sometimes they screw up other aspects of the electrical system that don't seem related at all.