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View Full Version : FYI: Possible Answer for Premature Engine Wear


Mike Bradley
August 9th, 2006, 10:20 PM
Here is a copy of an email my Joe Gibbs rep sent me today. Over the coarse of 18-24 months we've seem an unusual amount of premature camshaft failures. This bulletin gives you an insight to possible reasons.

Enjoy.

Mike

Joe Gibbs Racing Oil Tech Bulletin

Extended Drain Interval and other API licensed engine oils are not the same products as they were a few years ago.

As Comp Cams recently pointed out in a Tech Bulletin, "Today's engine oil is just not the same as it used to be, thanks to the ever tightening environmental regulations."1 The EPA, car manufacturers, and the American Petroleum Institute (API) have done a great job reducing emissions and extending the life of emissions control equipment. However, the reduction in emissions has coincided with a reduction in traditional, performance proven anti-wear additives (i.e. zinc dithiophosphates). In the years ahead, the levels of formulated anti-wear will be further reduced. While this is great for the environment, it is bad news for your racing engine.

As stated in the book "Lubrication Fundamentals","In heavily loaded applications (i.e. racing engines), flat tappet cam followers operate on partial oil films at least part of the time. Lubricants with anti-wear additives are necessary if rapid wear and surface distress are to be avoided. The oil additive Zinc Dithiophosphate is to provide anti-wear activity for the camshaft and lifters. With the increased use of roller follower cams (in production cars), the requirements for anti-wear have been changed to prolong the life of emission control devices."2

The increased RPM and related increase in valve spring pressure in today's racing engines require higher levels of formulated anti-wear, especially in flat tappet engines. Again, the book "Lubrication Fundamentals" sums this up, "Loading on the rubbing surfaces in the valve train may be high, particularly in high speed engines, where stiff valve springs must be used to ensure that the valves close rapidly and positively. This loading can result in lubrication failure unless special care is taken in the formulation of the lubricant."3

This is where Joe Gibbs Racing found ourselves in the late 1990's. The valve train loads in our flat tappet NASCAR Nextel Cup engines exceed 500 psi in order to turn over 9,000 rpm. The high loads and long duration races (up to 600 miles) required more formulated anti-wear chemistry than even the best API rated synthetic passenger car oils offered. Joe Gibbs Racing Oil was born out of the need for a high quality, synthetic oil that could protect both our flat tappet Nextel Cup and roller follower Busch engines without giving up horsepower. Over the last seven racing seasons, we've developed a family of lubricants that provide the necessary levels of advanced formulated anti-wear chemistry to protect highly loaded racing engines from break-in to endurance race conditions.

We've also learned a few things about oil that can help you make better educated decisions about which oil to use in a particular engine.

* Additives make a difference - As referenced earlier, having the correct additives in the correct amount formulated into the oil separates racing engine oils from passenger car engine oils. You wouldn't use a stock piston in a built race engine, and the same goes for oil.


* Surface finish matters - "The minimum safe film thickness is a function of the roughness of the surfaces. Rougher surfaces require thicker films (higher viscosity oil) to prevent contact of surface asperities through the film. On the other hand, the finer the surface finish, the lower minimum safe film thickness (lower viscosity oil) and the less clearance is necessary. Since film thickness decreases with increases in unit loading, if the minimum safe film thickness is lower as a result of finer surface finishes, the allowable unit loading is higher.”4 The improvement of surface finishes through chemical polishing and tape polishing has enabled JGR to lower the viscosity of oil we use without sacrificing wear. Especially at break-in, the better surface finish you begin with, the fewer problems will be encountered during break-in. The polished foot flat-tappet lifters currently available provide superior surface finish compared to non-polished lifters.

* Choose the correct operating viscosity – Viscosity is a measure of an oil’s resistance to flow, and viscosity decreases (flow increases) as temperature increases. With that in mind, the operating temperature of the oil plays a major role in the selection of the proper viscosity oil. Too high a viscosity oil can result in excessive heating and lower mechanical efficiencies. Too low a viscosity oil can lead to excessive metal to metal contact of moving parts. When oil is of the correct viscosity and has adequate anti-wear characteristics, wear due to metal-to-metal contact is kept at a minimum. As previously stated, improved surface finishes allow the safe use of lower viscosity oil for better cooling and improved efficiency (horsepower). In addition to operating temperature, engine speed (RPM) and load also effect the operating viscosity and film thickness of an oil. Higher engine loads (cylinder pressure) decrease film thickness, but higher engine speeds (RPM) increase film thickness. For more detailed explanations of how viscosity, speed and load change in relation to each other, please visit joegibbsracingoil.com.

What can you do? – Check your oil bottles for the API donut. If the oil you currently use carries an API donut, it probably lacks the amount and type of formulated anti-wear chemistry found in a true racing oil. Choose an engineered fluid like Joe Gibbs Racing Oil that’s designed to meet the higher anti-wear needs of your racing engine. Please refer to www.joegibbsracingoil.com for more technical advise and product descriptions, or call our tech line at 866-611-1820.

1 - Comp Cams, Technical Bulletin dated 11/28/05, Flat Tappet Camshafts

2 - Lubrication Fundamentals, Second Edition, By D.M. Pirro and A.A. Wessol, Published By Marcel Dekker, Inc., Copyright 2001 Exxon Mobil Corporation, Page 229

3 - Lubrication Fundamentals, Second Edition, By D.M. Pirro and A.A. Wessol, Published By Marcel Dekker, Inc., Copyright 2001 Exxon Mobil Corporation, Page 259

4 - Lubrication Fundamentals, Second Edition, By D.M. Pirro and A.A. Wessol, Published By Marcel Dekker, Inc., Copyright 2001 Exxon Mobil Corporation, Page 180

Media Contact: Joe Gibbs Racing Oil / Ed Fennell / 704-944-5153 / efennell@jgr18.com

This email and any files transmitted with it are confidential, and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information, and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute, or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake, and delete this e-mail from your system. If you are not the intended recipient you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited.

Hectic
August 10th, 2006, 08:31 AM
Good info,many people are using Rotella T as their regular oil for flat tappet cam applications on the street,it has one of the highest levels of Zink and it's not as expensive as the "race oil" versions.Some of the info that I have read talks about Zink hampering the catalytic converter's ability to do its job and the fact that most all vehicles offered during the last years are equipped with roller lifters therefore not needing the extra metal to metal protection needed for the flat tappets.I use Rotella during engine break ins but I may run it for a while in the Buick just to try it.