I'm running 18 volts because it's the simplest way to keep my voltage up. I have a 6V and a 12V in series.
12V (11.5 under load) is too low to keep voltage to the coil and fuel pump high enough for my car. Keeping 18V seems to add a bit to my MPG. I have not done any good "scientific-ish" testing so take my numbers with this in mind.
See this thread:
http://ecomodder.com/forum/showthrea...e-up-7551.html
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Vortex generators are old tech. My new and improved vortex alternators are unstoppable.
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