[Tigers] Motor Oil

[Tom Witt]

>From what I’ve read flat tappet cams aren’t really flat and neither are the lifters. The cam is ground with a slight angle on its surface and the lifter is slightly convex. Both enhance the spinning of the lifter on the cam. Many (I know I use to) likely assume the lifter stays relatively stationary and “slides” on the cam based on the normal description.  One product that I’ve heard about is GM EOS (engine oil supplement). This is the link (Summit) and the write up. http://www.summitracing.com/parts/nal-88862586  “ Protect your engine with a bottle of proven Chevrolet Performance E.O.S. additive to keep your engine running smoothly and efficiently. This Engine Oil Supplement is recommended to be installed before firing a new engine equipped with a Chevrolet Performance camshaft.  I used this when I broke in a new cam. In addition to the 2,000-2,500 RPM break in process I set the idle at about 1,000 RPM for the first 1,000 miles.

As far as the diesel oils go (Rotella etc.) I’ve heard that they too have reduced ZDDP also now that those vehicle are running some form of CATs. Maybe oil should be labeled like food so we know specifically what is in it. What I find interesting is I’ve never seen an additive bottle that stated not to use it in a modern (CAT) car.  Yet they are requiring it removed from oil to protect the CAT??? Hummm... .   The oil additive debate seems to follow the same course like the need for supplement vitamins.

From: Tod Brown via Tigers 
Sent: Saturday, November 14, 2015 2:19 PM
To: tigers at autox.team.net 
Subject: Re: [Tigers] Motor Oil

My understanding is that the most important issue with flat-tappet engines and lubrication is that
the initial break-in is crucial to longevity. For the first 1500-2000 miles of operation it is extremely 
important that the proper level of zinc additive (i.e. zddp) be provided so that cam surfaces, rings
and cylinder bores be allowed to seat themselves. Newer oils are too slick to allow the necessary
scuffing to take place, whereas the presence of zddp provides enough friction for the seating to 
take place. Once past the initial break-in, zddp is no longer as necessary. I have not seen a definitive
statement as to whether zddp is necessary after break-in but many sources recommend that an
oil with higher levels of zddp be used. 

I found the discussion at http://www.hotrod.com/how-to/engine/ccrp-0702-break-in-new-cam/
to be helpful. Note that, at the end of the article, there are some recommendations for oils with
higher levels of zddp, usually used in diesel engines. 

Cheers,

Tod Brown
B382002384LRXFE
TAC #864



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