<VV> ZDDP

[Mark Durham]

Ken, as time goes on the need for proper levels of ZDDP stays the same for
our flat tappet engines. The newer oils continue to have their ZDDP reduced
to meet EPA requirements for the Catalyic converters. If you have not read
or don't have Richard Widman's oil articles, here is  link:

www.*widman*.biz/uploads/Corvair_*oil*.pdf
Richard also emphasizes the need to keep the oil viscosity cose to that
engineers designed the engines to use, to get optimum protection.
That discussion is in his articles on viscosity at 100 degrees C and is in
the range of 9.3 to 12.7 CsT, or a 30 weight oil, or multigrade derivitave.

Also, a guy on the Corvette Forum did extensive research on the shear
strenght of oils. I circulated this around as well, on VV.
http://forums.corvetteforum.com/c3-tech-performance/3078239-quaker-state-s-new-defy-motor-oil-lab-test-and-wear-test-data.html
His focus was on shear strenght, which is a good point, however, its not
all the equation, because that changes as the oil ages. But, that is true
for all oils, so, its a good lace to start. One interesting fact that
passes by some folks is that good respected oils placed fairly low on the
shear tests. So, since our engines have been run on Brad Penn and Mobil 1
for decades with no oil related failures, it is proably safe to say most of
the oils on the list of those tested would be safe to use given the had the
required ZDDP in them.

In the end, for me, you make your own decision, but for me, I want the oil
that provides the best shear strenght, meaning resistance to shear under
high load, like on cam lobes, etc, and plus, I want the recommended ZDDP
which is sacrificial, meaning, it wears into the cam lobes, lifter faces,
cylinder walls and piston rings and is used when no oil is there to
lubricate, like on startup. So, there needs to be enough ZDDP in the oil to
last a oil change cycle, and the quality of the oil must also be high
enough to last a oil change cycle.

Personally, I am using the Valvoline VR 1 10W30 Racing oil, designed for
everyday use. It ranks #3, I think, in the oil shear tests for oils high in
ZDDP, in the second link above and aleady has the needed ZDDP in it. I buy
it by the case off Amazon Prime.

Mark Durham
On Thu, Oct 18, 2012 at 5:59 PM, Ken Clark <kcvair at hotmail.com> wrote:

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>
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> Not having heard anything about the zinc additve ZDDP lately I was
> wondering if anything has changed.  I've been at a couple of shows that had
> swap meet items and the older cars, but no mention of the zddp and no one
> was selling it that I could see.  Most auto suppliers that I've been to
> don't have it and some have not heard of it.  Just wondering as I'm about
> to start an engine that has been run very little since this became a
> concern.  Ken
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