Oil for flat tappets...good article

[Bill888]

Here's a good article regarding lower zinc levels in modern oils and what's needed in an oil for flat tappet camshafts.
http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/index.html

 

[Drew99GT]

Here is the key: "The reduction first started in the mid-'80s, and it has been a gradual process, but the latest API SM and GF-4 specs have reduced ZDDP content to such an extent that the new oils may not provide adequate protection for older, flat-tappet-equipped vehicles running NONSTOCK, PERFORMANCE CAMS AND VALVETRAINS."

Good article!

 

[KW]

Good article with lots of info.

 

[friendly_jacek]

You guys realize this was published several months ago, right?

 

[Gary Allan]

..and that's old news for someone who hasn't read it yet?? It's not like it's circa 2002.

The fundamentals of it have been discussed quite a bit, though.

 

[friendly_jacek]

quote:

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Originally posted by Gary Allan:

The fundamentals of it have been discussed quite a bit, though.

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Thanks for pointing it out.

 

[BrianWC]

Point being we've only had 2-3 Hot Rod threads about this article.

Don't feel bad, I got my copy out last night and re-read it. What's funny is that's one inconclusive article yet now if you notice they seem to be recommending HDEOs in lots more of their tech articles. Well, I guess if you want to protect those shoddy cams you're running....

 

[Ray H]

Even presuming the cams aren't shoddily manufactured, we're talking applications of high spring loads and obscene profiles. I'm not convinced even HDEO SL oils will fare significantly better with high profile cams forced to endure these loads in flat tappet applications. (But articles like these in mass market journals legitimize the cam makers' mantra, "It was the oil you used, you stupid, braindead bobblehead - warranty claim denied." when the inevitable happens.

)

 

[Drew99GT]

Exactly Ray! I know some classes of motorsport dictate non-roller valvetrains, but if one had the choice when building an old pushrod V8, why would you install anything BUT a rollerized valvetrain, from the lifters to the rockers?

 

[427Z06]

Greaser, I wouldn't worry about it. The Sequence IIIG test uses an pushrod pig-iron engine equipped with flat tappets of circa 1986 configuration. This was intentionally done to eliminate all concerns with valvetrain wear in older engines. Even the Japanese manufacturers, the ones who initially raised the concern, agreed.

On the other hand, if you have a pushrod pig-iron engine with an aftermarket hi-performance cam with very stiff valve springs and increased ratio rocker arms and/or poorly made offshore lifters, you're into different territory, and need to adjust accordingly.

Although that Hot Rod article was fairly well written, they obviously didn't talk to any Tribologist since they didn't even touch on the subject of ZDDP depletion. An engine built with looser fit forged pistons, ring gaps opened to the high side is going to deplete the ZDDP through the increased blow-by in addition to the effects of the hi-po cam, springs, high ratio rockers. You stack the deck like this against the oil and then try to run OCIs like your wife's stock Honda Civic, and you'll be in for a surprise.

 

[buster]

Once again, 427 makes an excellent point. As you increase power with after market blowers/turbos etc., you'll also have to adjust your viscosity, I would think. I would have a tendency to believe that very few of these guys know anything about lubrication and seldom if ever have UOAs done. This is also something to take into consideration.

Of course the possibility always exists that more ZDDP is better for older style engines, and not the more modern engine designs. However, as 427 stated, the Sequence testing done so far does not reflect this.

 

[BrianWC]

Now, now, we can't have it both ways. These are the same folks everyone laughs at for running 20W50.

 

[Gary Allan]

quote:

---

Originally posted by BrianWC:
Point being we've only had 2-3 Hot Rod threads about this article.

Don't feel bad, I got my copy out last night and re-read it. What's funny is that's one inconclusive article yet now if you notice they seem to be recommending HDEOs in lots more of their tech articles. Well, I guess if you want to protect those shoddy cams you're running....

---

Maybe they read BITOG

quote:

---

Even presuming the cams aren't shoddily manufactured, we're talking applications of high spring loads and obscene profiles. I'm not convinced even HDEO SL oils will fare significantly better with high profile cams forced to endure these loads in flat tappet applications. (But articles like these in mass market journals legitimize the cam makers' mantra, "It was the oil you used, you stupid, braindead bobblehead - warranty claim denied." when the inevitable happens.

)

---

Well, I would assume that one of two things need to occur. Either cam mans need to assure that there is an oil suitable for long life in a high spring pressure environment.

..or would be hotrodders need to understand the longer term costs of owning a muscle car/street racer.

Since cam mans don't mind selling cams ..I think neither will occur.

 

[Greaser]

Well my 2001 and 1999 Jeep engines use flat tappet technology so it's a SL rated HDEO (Esso xd-3) for me.Rather change out a cat or sensor than have my vavle train degrade.

 

[427Z06]

quote:

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Originally posted by BrianWC:
Now, now, we can't have it both ways. These are the same folks everyone laughs at for running 20W50.

---

Sure, but did you ever notice the bearing clearances in many of the engine building articles. They have to run 20w50 just to get decent oil pressure.

 

[bigbadbowtie]

I know that Comp Cams actually recommends the use of diesal oil for breaking in flat tappet cams.

I think the reason people choose not to run a retrofit roller valvetrain in their older cars/hotrods is the cost. It adds up QUICK!

I myself will never run a performance/max effort engine with out a roller valvetrain. Its worth the extra $$$ to me.


EDIT.... 427Z06... I used to live in Cedar Park.
I sure miss it.

 

[BrianWC]

quote:

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Originally posted by 427Z06:

quote:

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Originally posted by BrianWC:
Now, now, we can't have it both ways. These are the same folks everyone laughs at for running 20W50.

---

Sure, but did you ever notice the bearing clearances in many of the engine building articles. They have to run 20w50 just to get decent oil pressure.

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I know, it's just odd to see someone on here with any experience advocating thicker is better in any circumstance.

I'd love to start my own project car and build up some good old American iron but with two kids and a nice mortgage....the Johnny Cash song "One Piece at a Time" comes to mind.

 

[bigbadbowtie]

The shop that built my old 355 short block recommended 20-50. That was a flat top, pump gas, solid roller engine was spun 7400 rpm and was hit with heavy doses of nitrous.

 

[friendly_jacek]

quote:

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Originally posted by 427Z06:
The Sequence IIIG test uses an pushrod pig-iron engine equipped with flat tappets of circa 1986 configuration. This was intentionally done to eliminate all concerns with valvetrain wear in older engines. Even the Japanese manufacturers, the ones who initially raised the concern, agreed.

---

427, you convinced me that the IIIG sequence guarantees quality oil for most applications. Yet I remember you saying that some oils barely pass it and some score below half of the allowable wear of 60um. We know that schaffer oil belongs to the second category. Since you sound like an insider, can you give us some hints what the other “better” oils are?

If not (trade secrets), can you tell us what are the characteristics of the “better” oils:
higher EP additives (moly, boron), 800 vs. 600 ppm P, different base oil, resistance to thickening vs. ability to thicken (up to allowable 150%), etc.

Thanks!

 

[427Z06]

quote:

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Originally posted by friendly_jacek:
Since you sound like an insider, can you give us some hints what the other “better” oils are?

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I wish I were. Terry and Molakule are the real industry insiders. But like many professionals, I'm sure they're restrained by non-disclosure agreements and/or legal concerns.

What information I accumulate is from engineering colleagues and friends, things I ran across while employed in the automotive industry, what people like Terry and Molakule teach us, and good old engineering detective work from what publications I can get my hands on and through the internet combined with my years of racing and building engines as a hobby.

In short, I'm in the dark like everybody else on what oil formulations are the best. What data I have seen was coded and revealed very few details on the formulations or the manufacturers.