If you’re planning an alternator upgrade, knowing what is needed can go a long way to helping get good results without overspending.

The week is almost over, and once again, another Thursday has arrived. I don’t know about you, but since the weekend is getting close, I have already planned what I’ll be working on in the garage. If your garage plans include upgrading the electrical and charging system on your classic, we can help with that. Once again, we celebrate another editorial look-back, and jump into the way back machine to open the Power Automedia vault that houses our vast collection of articles and revisit another great informational piece.

In this Throwback Thursday, we’re taking a small jump back to November 2013. That’s when we reached out to the folks at Tuff Stuff Performance and got some input about some truths and myths of one-wire alternators. The subject is still relevant, and that’s why I thought One-Wire Alternators: Are They Better Or Just Easier To Hook up? was a great article for this week’s Throwback.

As you might assume, the concept behind a one-wire alternator is that there is a single wire used to connect the alternator to the battery.

When the classic cars we enjoy were new, the output of the alternator was simply enough to sustain the battery power needed to run the engine with the headlights on. Items like fog lights, driving lights, stereo amplifiers, and other high-powered accessories hadn’t really hit the market. In fact, it would several years until they did.

Now they are a mainstay, and people installing them to enhance the driving enjoyment of their seasoned ride. They are driving their classic cars more often, and the addition of these power-sapping electrical components requires more amperes. One way to upgrade an electrical system is to install an alternator that delivers more of those needed Amperes. What many fail to consider, is that vintage wiring in your car probably can’t handle more than the 45-60 amps the factory alternator were putting supplied. The original article gets deeper into that subject. One solution to the charging dilemma is to upgrade to a single-wire alternator that puts the power directly to the battery – and only when the engine is running.

That single post is the only power connection required, but you will need to be sure the alternator is properly grounded.

Having the right amount of power output does require some planning and forethought. While running a 200-amp alternator isn’t going to overcharge a battery, it is equivalent to installing a larger fuel tank: the capacity increases, but you’re still using the same amount of fuel when you drive. Likewise, high output alternators aren’t going to improve the quality of electrical components because they consume the power they need and nothing more. They will improve their effectiveness when the alternator is installed correctly, but when a 100-amp alternator will suffice, 200 amps will do very little other than empty your wallet.

The wiring in most classic cars will not be sufficient to carry the additional output of the larger amperes alternator.

There is a lot more information in the original article, and if you’re looking for some insightful suggestions from a professional source, check out One-Wire Alternators: Are They Better Or Just Easier To Hook up? You’ll be glad that you did.