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@Carlos P , Michael Pickett and others have done a remarkable job of shielding you from the bloodshed and violence that usually erupt here whenever oil is discussed. You can tell they've had to go to great lengths if they're resorting to words like 'obstreperous'.
But I feel they have done you something of a disservice in the course of protecting you from the ugliness of war.
There are a few thorny, technical issues at the root of this. Most of us don't understand these very much, but's it's important that you at least sound like you do. You need to have a few key terms handy and ready to toss into the conversation whenever this comes up amongst car guys, if you're to be accepted as a legitimate Speedster owner.
As far as oil is concerned, people who claim to know say our ancient VW engines differ from modern ones in one essential way. Modern engines can use all sorts of different modern oils because they have something called 'hydraulic valve lifters', while our ancient engines have something called 'flat tappets'. Now, I don't pretend to know what that means (and you don't have to, either), but just toss the phrase 'flat tappets' into the conversation in a knowing kind of way and you'll be fine.
Anyway, because of these so-called flat tappets, in the old days all oil supposedly had stuff in it to protect the flat tappets and some of that stuff was zinc. 'Zinc' is the other word you need to know to toss into the conversation to sound like you know what you're talking about. That's pretty much it. Just say 'flat tappets' and 'zinc' every once in a while, in an off-handed kind of way, and you're good.
By the way, it's starting to come out now that this whole story about flat tappets and zinc was made up out of thin air by secret departments of Russian intelligence agencies, and disseminated on social media in a very clever campaign to set us at each others' throats and create general mayhem among car guys - who usually get along with each other just fine.
As for which oil to use, I think the best advice is 'clean oil is better than dirty, and dirty is better than none'. That's all you really need to know.
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