I am kicking and screaming into the 21 century. I install a grid and sportsman racepak, a 16 volt battery and alternator. The racepak says the alternator is putting 19 volts back to the battery. Holly says the grid will only handle 18 volts. Anyone with good or bad results in this situation? I have removed the belt from the Alt.

Not expert but I would stay within the limits.

XS has an alternator that you can turn down. i ran one with 16v and frankly hated the 16v. No reserve and PIA with electric pump fuel pressure...went back to 12v and added another red top and it cranks and worked just as good in that department. And you can not kill the two 12vs.

Also with the XS alternator the adjuster seemed cheap and had one go bad.

Good luck - and I say 2 12v for the win.

It will be fine. My daughter has an alternator on her car and the grid. No issues at 18+ volts. After going to a 16v setup I'll NEVER go back to 12v again. The engine cranks faster (two 12v batterys will not crank as fast as one 16v) and I've had zero issues with water pump or fuel pumps as most are now designed to run on 16v. If there's ever an issue, you can always get a step down box, readily available. 12v is for street cars only.