Like others have already said....16 volts is too high. Have the alternator and the charging system checked out, before you toast all things electrical. My one wire alt went berzerk a few years back on a run to Lou'ville, fried the internal regulator, blew the battery and scorched a lot of wiring. It was charging at 18 for just a few moments before I could get it shut down, which was already too late. Didn't damage the HEI, but everything else was ugly.