[Spridgets] ZDDP

[John.Deikis at va.gov (Deikis, John G)]

My understanding (quite limited) is that ZDDP breaks down into
phosphorus and sulfur that provides the extreme pressure protection by
adhering to the sliding metal surfaces of the cam-tappet interface. Too
much phos and sulfur actually attack the metal and cause eventual
degradation.

FWIW: the best recent article I've come across that summarizes the
issues is on a Corvette site and worth reading. The author avoids a lot
of the earlier hysteria and panic that characterized coverage of the
topic in the popular press.



http://www.corvetteactioncenter.com/tech/oil/index.html



Cheers!

JohnD



From: WeslakeMonza1330 at aol.com [mailto:WeslakeMonza1330 at aol.com]
Sent: Thursday, May 26, 2011 12:54 PM
To: Deikis, John G; spridgets at autox.team.net
Subject: Re: [Spridgets] ZDDP



What happens if you have too much?





In a message dated 26/05/2011 14:40:55 GMT Daylight Time,
John.Deikis at va.gov writes:

        5.       Too much ZDDP is also bad for cams and tappets. The
sweet spot
        is between 1300 and 1500 p.p.m.