An interesting test on lack of ZDDP in oil and flat tappet cam engines...

[Squirmn German]

http://blackstone-labs.us1.list-manage1.com/track/click?u=f641390cba42169db49e0cd6e&id=dea9899ac8&e=c3f4cd4f22

[fixer44]

I don't think his results with a GM V8 can be directly applied to the VW engine. The 350 has hydraulic lifters and each cam lobe only operates 1 valve.
I would think the VW cam lobe is under way more pressure and stress with solid lifters and operating two valves. Good article but I will stick with Brad Penn.

[Ohio Tom (DdK)]

I have a few things to say about that....

1. The author discounts the problem in that it may occur on only one cam lobe, and not all cam lobes. This is no suprise to me. It has to do with work hardning the face of the cam and lifter so that wear is minimized. If a particular lobe doesn't get broken-in properly, it will fail prematurly leaving the others to live just fine.

2. Aircraft engines, infact do have issues with cam lobe wear related to the ZDDP in the oil. Pick up any aircraft monthly mag and you'll read about it.

3. the authors mention of the "scientific method" is noteworthy, however, he doesn't follow it very well in his testing. There are many assumptions and cause-effect relationships that are not necessrily proven knowlege.

4. The test engine is a mild/stock chevy 350. A motor known for it's abiltiy to withstand almost any abuse you can throw at it... (like using old powersteering fluid for oil.) Don't ask.
Quite different than a heavy springed, HiPo VW motor.  

There are several things at work to cause a cam lobe failure. One of them is the oil's ability to lubricate.

My "scientific method".. I install new CB 2298 cam with CB L/W lifters and Brad Penn oil. Motor is used for 3 seasons of heavy drag racing action 8,000+ rpm every time it runs.
This is normally enough to kill a cam/lifter combo if anything isn't right.
What I found:
Only a few thou of cam lobe wear is measured, lifter faces look like polished mirrors...

[Squirmn German]

Yes, good points all around. I never said i agreed with his findings and such, just passing along the article. By the way, he is the owner of Blackstone laboratories. One of the best oil testing facilities.

[Donny B.]

Remember aircraft engines don't rev very high and for the most part run at a constant rpm.  Not like an automotive engine.  Apples and Oranges....!

[WV-VW]

Aircraft monthly?? I'd much rather "read" Hustler, or ....(sorry, we're talking worn out tappets not tap worn..Never Mind)