Regulator issue if at 18 volts?

Thats what worked for my car. Since the voltage regulator replacement I have had no issues. By the way, I do have a ground strap on my motor. It goes from a bolt on the back of the head to one of the bolts on the blower motor. One thing that has made a major difference was new battery cables and ends. I used to have that 'surge' where the lights got dimmer at a stop light and when I stepped on the gas they got brighter. I cleaned the ground area on the motor mount bracket where the ground cable goes as well as the area that the small ground wire that runs from the battery to the core support right near the battery goes, cleaned all other connection areas and no more surge issues either. Just a little tip that may help. Good luck!!
Chas.