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Talking to a guy with 30 yrs VW experience who has a shop near me and he said DONT use synthetic oil,a few years ago VW/Porche sent out a memo re: do not use synthetic oil on older engines Hmmmm?

Absolutely use synthetic oil. Just don't use street oil. It's a zinc thing. Search for threads here regarding zinc additives for details.

Long story short, synthetic racing oils have the additives needed for flat tappet valve lifters. Current street oils will wear a cam and lifters in short time.

in a standard vw motor synth oil will leak like crazy. alum case, steel drain plate. two differant metals expanding at differant rates, causes leakes. on my first vee I swapped the steel drain plate for a al. one to go with the sump ext. no more leaks. something to think about and look to see what you have.
My 74 thing, built up 1835cc doesn't leak a drop???? royal purple 5/30. how did I do that? allways check it twice to make sure there is oil in it.
"if a vw is not leaking, it is out of oil."
THOR

If an engine has leaks it will leak MORE with a synthetic. This is because a synthetic stays thinner when cold. If you have no leaks a synthetic won't leak anymore than a base stock oil. However even with some leaks a synthetic far surpasses a base oil in almost every way. More HP, especially in the first few laps until lthe oil temp reaches 160 or so. (The same is true for the transaxle.) Then they are about the same. I can show you chassis and engine dyno runs at those temps and you are talking as much as 3+HP in a Vee.
At <300 deg a base oil is destroyed. Synthetics will go 400+ and still provide lubrication. (and keep in mind that the temp you measure is in the sump. At the bearing it is much hotter) Their shear properties are better, longevity better and more.

Much of the leaking issues are old legends that started when synthetics were new. They didn't have the additives that kept the gaskets swelled. This was fixed years ago. For a water cooled street car, synthetics are an overkill in most environments. On an acvw I would NEVER run anything but a synthetic. BTW, you should buy an "Off Road Use Only" synthetic. (Mobile, Valvoline, Red Line, etc.) These are the only ones that contain sufficient zinc for a flat tappet cam. Most all of the zinc has been removed from over the counter street oils due to catalytic converter and 02 sensor contamination.