24.02.2013, 21:27
Denne tråden her synes jeg var veldig lærerik og det gjelder også bilene våre som ikke har roller tappets til ventilene feks OM617. Jeg har ikke lest hele 
den er tross alt på 97 sider.
Since the introduction of the new CJ-4 / SM motor oils, there has been lots of discussion about what to do. For those of you who do not know, the latest motor oil formulations have significantly reduced the anti-wear additive ZDDP (provides phosphorus and zinc).
Per SAE papers, approximately 1400 to 1500 ppm of Zn and P are needed. This level needs to be adjusted based on the levels of detergents present as well to prevent premature wear of rotating parts like camshafts in cars that have flat tappets (like our older Porsches). [edited 11/3/2008]
Newer cars have roller tappets to help save fuel. As a side benefit, they do not require the level of ZDDP that non-roller tappets require. Until the advent of the CJ4 / SM grades now currently offered, the ZDDP Levels of quality motor oils provided the phosphorus and zinc we needed.
Much of this is discussed on Charles Navarro's Web page http://www.lnengineering.com/oil.html. Steve Weiner and I have discussed the impact of lowered ZDDP on engine longevity as well.
Link:
http://forums.pelicanparts.com/porsche-9...-oils.html
den er tross alt på 97 sider.Since the introduction of the new CJ-4 / SM motor oils, there has been lots of discussion about what to do. For those of you who do not know, the latest motor oil formulations have significantly reduced the anti-wear additive ZDDP (provides phosphorus and zinc).
Per SAE papers, approximately 1400 to 1500 ppm of Zn and P are needed. This level needs to be adjusted based on the levels of detergents present as well to prevent premature wear of rotating parts like camshafts in cars that have flat tappets (like our older Porsches). [edited 11/3/2008]
Newer cars have roller tappets to help save fuel. As a side benefit, they do not require the level of ZDDP that non-roller tappets require. Until the advent of the CJ4 / SM grades now currently offered, the ZDDP Levels of quality motor oils provided the phosphorus and zinc we needed.
Much of this is discussed on Charles Navarro's Web page http://www.lnengineering.com/oil.html. Steve Weiner and I have discussed the impact of lowered ZDDP on engine longevity as well.
Link:
http://forums.pelicanparts.com/porsche-9...-oils.html