John:

Well said anyway.  All very true.

John Connolly, Aircooled.Net wrote:

>Synthetic oils are fine. I do want to clarify something though. I have
>always promoted good synthetics (the heat rejection issue is BS, we have
>tested them; it may have been true in 1980, but in 2003 when we tested it
>was proved (to us) to not be an issue). YMMV.
>
>But you have to make sure you match the oil to the engine. When I say that,
>I am specifically referring to the bearing clearances, which is also related
>to engine life. Modern engines, which "like" synthetics a lot more then the
>older ones, have much more accurate and tighter bearing clearances due to
>improved assembly line machining. It may open some eyes to hear that NASCAR
>engines break the engines in on peanut oil, and race with 0-40 oil, running
>10500RPM for 500 miles at a crack. Try to do this with dino oil and the
>engine is history real quick. Thin oils move thru the journals quickly,
>removing heat. Yes the oil pressure is lower, but oil pressure doesn't
>lubricate the journals. Set your bearing clearances to .0005" and run 20-50
>oil and you'll have great oil pressure, and tell us how long the engine runs
>before it siezes from overheated journals! You won't need to count it in
>thousands of miles, simply counting you fingers and toes should suffice. ;-)
>
>Watercooled engines can run "thin" oils easier then aircooled, because
>watercooled engines run in a closer temperature range then their aircooled
>cousins. More temp range means more clearance range in the engine. A
>combination of too much clearance and too thin an oil means BOOM. Running
>tight clearances with thick oils means BOOM too, you have to be in the
>middle somewhere for everything to be happy.
>
>You are crazy to run straight weight IMO, oils have come a long way in 30
>years; and for those that say they do it because the owners manual says so,
>the owners manual is how old? ;-)
>
>Factory engines from VW (aircooled) come with 5-30 or so in them last I
>checked, and that's what the owners manual says to run too. Aircooled
>engines can run cooler with thinner oil, but like I said before too thin and
>BOOM.
>
>I can't believe I'm adding to the oil thread, I promised myself I wouldn't
>do it LOL.
>
>John
>Aircooled.Net Inc.
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