<VV> Concerns about using the latest rated oil in pushrod

[Phil Fairman]

Group;

Just wanted to echo Paul Fox's post about the changes in motor oils that effect flat-tappet engines.....this is just now starting to get some exposure. What has happened is that the oil companies, in response to the EPA's demands to reduce Phosphorous & Zinc additives in motor oils (especially those rated "Energy Conserving, Like 5W-30, 10W-30, etc) because the life & effectiveness of catalytic converters are reduced when these compounds escape as blowby into the exhaust have dropped the levels of these compounds (referred to as ZDDP) which are needed to prevent scuffing & wear on flat-tappet engines, to a point where many of the oils that we have relied on and trusted for many years, will no longer provide the protection needed. This has NOT been publicized by the oil companies as most "modern" engines (in the last 20 years or so) now use roller tappets. I feel that the oil companies have been somwhat irresponsible in not notifying the users of these oils that a change has occurred. There have been a LOT of premature cam failures because of this. I was made aware of this through a website: http://www.lnengineering.com/index.html

This is primarily a Porshe site and the owner, Charles Navarro has done rather extensive research on oils as he rebuilds $15,000.00 Porsche engines.......there is much information on the current oil situation if you click on the "oil" link on the front page. 

The bottom line here, is that, as an owner of a "vintage" engine, that was designed to use oils with necessary additives, you must now become a bit more knowlegable about oils in general to, if you will pardon the phrase "Keep your Corvair alive". After several long conversations with Charles Navarro, I have switched from Mobil-1 10W-30 to Brad Penn Semi-Synthetic 10W-30 "Racing" oil. I considered using GM EOS or the STP Red additives, but, the risk here as "how much?". 
I understand that some of the 15W-40 Diesel oils have now been changed from CL4 & SL formulations which have enough ZDDP to the new CJ-4 API standard which may not. You can no longer assume that the oil that you have trusted for years or even generations will still provide what your Corvair engine needs.....the times they are -a- changin! Just as an aside, Brad Penn makes a dedicated SAE 30W oil specifically formulated for break in of newly built engines with a generous dose of ZDDP to insure proper cam/lifter lubrication. 

Phil