So if I have an aftermarket internally regulated 150 amp alternator, I should still leave the external regulator and capacitor connected? Or do I need to put back my original delcotron alternator back on to get it working right?
It should work with either alternator.You don't want the external regulator connected. Try running it without the cap and see if it is noise free...
If you are not using the OE or a mechanical regulator, the regulator cap will have nothing to do. Sort of like some Govt. employed friends of mine. A lot of Internally regulated alts have a cap in them. I don't know what alt you have, but it never hurts to add a cap.