Latest from Castrol re flat tappet engines...

I have run 20-50W for a long time and mainly for the summer heat, but I agree a shift to the 05 -50W is probably a good idea....

Good stuff!!!

 

Thanks Jim for the info.

CK

 

I too have been using a 20-50 blend, Valvoline Racing in the crankcase for the past 5 years but after reading the Ferrari Service Bulliten 00-25 dated 6-15-88 (GEEZ) you make the call. Great Information from castrol thanks.
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That's an old bulletin - 10 years later Ferrari said 5W40 was fine for all V8's regardless of what year. The ZDDP thing is all about selling something, not about what the engine needs. These cars have cams that are very mild by HP standards, the idea that they need a lot of phosphorous/zinc is misguided.

Mobil and other oil companies have a lot of CURRENT data available re this and any oil with more that around 800PPM of those additives is plenty for these engines. You need to look at the REQUIREMENTS, NOT what somebody who's trying to sell you something says you need.

 

Sorry, but the ZDDP thing is not about selling something; this is a very real problem made accute with the introduction of the API SM classification (and "Energy Conserving-I", "Energy Conserving-II", and GF-4). Oils that meet SL alone (not SM) can be formulated with enough zinc/phosphorous (ZDP) to be safe for flat tappet engines; unfortunately, the limits in place with SM are substantially more restrictive and the oils can not contain sufficient ZDP to protect the cams on flat tappet valve trains: flat tappet valve trains generally require 1200-1500ppm to be safe.

In SM oils, the ZDP is replaced by "friction modifiers" (moly or boron), which provides excellent protection for lower contact pressure applications, but moly does not provide the protective action that zinc/phosphorous do for high contact pressure applications (flat tappets). Unfortunately, motor oils for general highway automotive use are now mandated to have greatly reduced of the critical zinc/phosphate ingredients needed for protection; notably, motor oils for off road and motorcycle applications are exempt from these rules.

Thus there are three ways to beat this problem:
1) Add a ZDP additive package to your SM oil of choice. You're on your own with this, as you're now formulating your own motor oil.
2) Switch to a racing oil, which generally quote actual zinc/phosphate quantites on the spec sheet. This would work, but as racing oils don't have much ability to handle condensation and other aspects of typical road use, you will need to drain your oil very, very frequently - and even with very frequent drain intervals, you are still running a substantial risk.
3) Switch to a motorcycle oil, such as Mobil 1 Racing 4T. These oils are exempt from the EPA regs and are designed for flat tappet valve trains.

I've seen lots of discussion on oil on this forum, but all the discussion seems centered on viscosity, the most basic of motor oil components. At this stage of the environmental game, the additive packages are far more important than base viscosity....

-frank

 

Hmm... That doesn't quite add up. Valvoline VR-1 20w50 is SM rated, and contains 1200ppm of Zinc.

 

What doesn't add up is the claim that the SM rating requires low zinc levels, when VR1 20w50 is both high in zinc and SM rated. The fact that it is marketed as 'racing oil' is irrelevant (and it doesn't contain sufficient calcium levels to be a true racing oil anyway)

 

"Sorry, but the ZDDP thing is not about selling something; this is a very real problem "

I am not an oil expert by any stretch but I have done a lot of reading about this subject from engine and oil manufacturers. From everything I have read, it is a problem for engines with high lift, fairly radical cam profiles. It is not an issue for cars that have what most of us would refer to as street cams. Our 3x8 motors have quite mild camshafts and, per what I have read, there is no real need for high phosphorus/zinc levels beyond around 800 PPM. Mobil One 0W40, which I now use, has considerably more than that.

As you noted, adding ZDDP or whatever to oil is, according to engine and oil experts, a bad idea because you are basically reformulating the oil and, like most things, more (ZDDP) is NOT necessarily better. Additionally there have been some studies showing that adding ZDDP may not actually go into suspension with the oil, ending up as a "sludge" which does more harm than good.

I would never consider adding ZDDP to oil any more than I would use STP or any other additive. If I felt the 328 needed more zinc/phos, I would use an oil that had a higher content than Mobil One 0W40 contains but from my research, I don't see any issue at all for these engines.

 

Badman, apologies, my post is perhaps over simplified. It's actually quite complex as to how EPA regs on cat life have trickled down through the auto manufacturers to the lube oil manufacturers through various standards and goals.

API SM can be met as a standalone criteria by a high ZDP oil, but other criteria such as GF-4 mandate strict limits on phosphorous, so an oil can't meet GF-4 and SM with sufficient phosphorous for our valve trains. But even that statement is a simplification: ZDP limits vary by other product criteria, such as viscosity. The way things all work out is simple, though: you won't find a road-use automotive oil that is SM branded that has 1200+ppm zinc/phosphorous. You WILL find off-road, motorcycle, and diesel (as someone else mentioned), motor oils that meet SM and have 1200+ppm zinc. (e.g. the Mobil 1 motorcycle oils.)

Apologies for the confusion - it's a large and complex subject, a worthy product of the government that caused it!

-frank

 

gentlemen,,,i have finally got to sit and read through this thread,,,im a layman,when it comes to motors...and i think i understand what you fellows are talking about,,,i have never heard about what level of zinc a particular oil has or doesnt have,,,i just know the basics when it comes to oil....i have been using valvoline racing 20/50 petroleum based oil for 12 years,,changing my oil every 2500 miles without a hitch,...my mechanic used mobile 1 15 / 50 oil for the first time,,on my last 30k service april of 10,,,my car has 88k miles,,should i stick with mobile 1 or go back to valvoline 20/50.,,when my valves were adjusted...my guy said only one exhaust and one intake had to have new shims...and nothing was mentioned about any camshaft wear...the cam timing was set ..and the car is running great....i asked craig at fast cars about the oil change intervals with mobile 1 synthetic,,,he said 5000 miles,,,,im thinking maybe 3000-3500 max,,any thoughts would be appreciated,,,,Brett 89 328 GTS

 

Well, if old tractors have a problem then I'd have to admit that the radical cam profile thing may not be the issue that some of the things I have read seem to make of it.

OTOH, here's a quote I copied from GM that, IMO, pretty much explains the whole thing in a fair bit of detail. Whether someone chooses to accept it or not is a personal issue. I copied the entire thing though the ZDDP part is toward the end.



"Over the years there has been an overabundance of engine oil myths. Here are some facts you may want to pass along to customers to help debunk the fiction behind these myths.

The Pennsylvania Crude Myth -- This myth is based on a misapplication of truth. In 1859, the first commercially successful oil well was drilled in Titusville, Pennsylvania.
A myth got started before World War II claiming that the only good oils were those made from pure Pennsylvania crude oil. At the time, only minimal refining was used to make engine oil from crude oil. Under these refining conditions, Pennsylvania crude oil made better engine oil than Texas crude or California crude. Today, with modern refining methods, almost any crude can be made into good engine oil.

Other engine oil myths are based on the notion that the new and the unfamiliar are somehow "bad."

The Detergent Oil Myth -- The next myth to appear is that modern detergent engine oils are bad for older engines. This one got started after World War II, when the government no longer needed all of the available detergent oil for the war effort, and detergent oil hit the market as “heavy-duty” oil.

Many pre-war cars had been driven way past their normal life, their engines were full of sludge and deposits, and the piston rings were completely worn out. Massive piston deposits were the only thing standing between merely high oil consumption and horrendous oil consumption. After a thorough purge by the new detergent oil, increased oil consumption was a possible consequence.
If detergent oils had been available to the public during the war, preventing the massive deposit buildup from occurring in the first place, this myth never would have started. Amazingly, there are still a few people today, 60 years later, who believe that they need to use non-detergent oil in their older cars. Apparently, it takes many years for an oil myth to die.

The Synthetic Oil Myth -- Then there is the myth that new engine break-in will not occur with synthetic oils. This one was apparently started by an aircraft engine manufacturer who put out a bulletin that said so. The fact is that Mobil 1 synthetic oil has been the factory-fill for many thousands of engines. Clearly, they have broken in quite well, and that should put this one to rest.

The Starburst Oil Myth -- The latest myth promoted by the antique and collector car press says that new Starburst/ API SM engine oils (called Starburst for the shape of the symbol on the container) are bad for older engines because the amount of anti-wear additive in them has been reduced. The anti-wear additive being discussed is zinc dithiophosphate (ZDP).

Before debunking this myth, we need to look at the history of ZDP usage. For over 60 years, ZDP has been used as an additive in engine oils to provide wear protection and oxidation stability.

ZDP was first added to engine oil to control copper/lead bearing corrosion. Oils with a phosphorus level in the 0.03% range passed a corrosion test introduced in 1942.

In the mid-1950s, when the use of high-lift camshafts increased the potential for scuffing and wear, the phosphorus level contributed by ZDP was increased to the 0.08% range.

In addition, the industry developed a battery of oil tests (called sequences), two of which were valve-train scuffing and wear tests.

A higher level of ZDP was good for flat-tappet valve-train scuffing and wear, but it turned out that more was not better. Although break-in scuffing was reduced by using more phosphorus, longer-term wear increased when phosphorus rose above 0.14%. And, at about 0.20% phosphorus, the ZDP started attacking the grain boundaries in the iron, resulting in camshaft spalling.

By the 1970s, increased antioxidancy was needed to protect the oil in high-load engines, which otherwise could thicken to a point where the engine could no longer pump it. Because ZDP was an inexpensive and effective antioxidant, it was used to place the phosphorus level in the 0.10% range.

However, phosphorus is a poison for exhaust catalysts. So, ZDP levels have been reduced over the last 10-15 years. It's now down to a maximum of 0.08% for Starburst oils. This was supported by the introduction of modern ashless antioxidants that contain no phosphorus.

Enough history. Let's get back to the myth that Starburst oils are no good for older engines. The argument put forth is that while these oils work perfectly well in modern, gasoline engines equipped with roller camshafts, they will cause catastrophic wear in older engines equipped with flat-tappet camshafts.

The facts say otherwise.

Backward compatability was of great importance when the Starburst oil standards were developed by a group of experts from the OEMs, oil companies, and oil additive companies. In addition, multiple oil and additive companies ran no-harm tests on older engines with the new oils; and no problems were uncovered.

The new Starburst specification contains two valve-train wear tests. All Starburst oil formulations must pass these two tests.

- Sequence IVA tests for camshaft scuffing and wear using a single overhead camshaft engine with slider finger (not roller) followers.

- Sequence IIIG evaluates cam and lifter wear using a V6 engine with a flat-tappet system, similar to those used in the 1980s.

Those who hold onto the myth are ignoring the fact that the new Starburst oils contain about the same percentage of ZDP as the oils that solved the camshaft scuffing and wear issues back in the 1950s. (True, they do contain less ZDP than the oils that solved the oil thickening issues in the 1960s, but that's because they now contain high levels of ashless antioxidants not commercially available in the 1960s.)
Despite the pains taken in developing special flat-tappet camshaft wear tests that these new oils must pass and the fact that the ZDP level of these new oils is comparable to the level found necessary to protect flat-tappet camshafts in the past, there will still be those who want to believe the myth that new oils will wear out older engines.
Like other myths before it, history teaches us that it will probably take 60 or 70 years for this one to die also."

Bob Olree – GM Powertrain Fuels and Lubricants Group

 

I really don't understand the issue here with the lack of ZDDP in modern oils.

Anybody would think with these threads that modern engines do not have flat tappets, but many do ... and guess what they have NO problem.

How can Castrol say this?:

... BS, I own 2 and know of many????? Confused. A 458 engine is a flat tappet design ... isn't it? And so is the current Chev V8 ... so IMO this discredits Castrol straight away!

I have a Suzuki GS500 motorcycle and a Toyota family car that both have normal flat tappets and the motorcycle in particular has reasonably aggressive cam lobes and I run it on normal modern motorcycle oil and no wear issues at all. I did adjust one valve clearance but only by one shim thickness so we are talking 2 thou (I only did it because it bugged me but it was like that when I got it and 25,000 km's later was still the same), and with the Toyota when I checked the valve clearances at 100,000 miles not one was out of spec.

All those way more powerful motorcycle engines than mine (say R1, R6, GSXR1000, GSXR600, etc.) have very aggressive cam profiles and no wear issues ...

So again where is the problem? ... from my experience there is no problem.
Pete

 

Old English engines have always used soft metals (remember their moto, "can we make it even cheaper") ... won't be a problem in ANY Italian engine. Some old English engines don't even have valve seat inserts, they run the valves directly on the cast iron head ... and thus cannot run on unleaded fuel.

Replace the cam/cam followers (because other than Jaguar, MG TwinCam, Lotus, Ford BDA we won't be talking overhead cam) with ones made out of decent metal and problem solved (note because we are talking pushrod engines the cam profile will not be aggressive because there usually is a rocker ratio to enable the cam to be soft, so this supposed issue has nothing to do with cam profiles, it is cr@p materials IMO). Usually when you rebuild one of these old English engines you have to practically remachine everything anyway if you want a decent engine ... which they can be. Take the Triumph straight 6 ... balance the crank and you get a completely different engine, wonderfully smooth. Triumph must not even bother balancing at all .

Here is proof that it is the hardness of the camshaft that is the problem NOT the oil (ie. ZDDP enabled the cheap @rse manufacturers to get away with running soft components):

I bet that any Ferrari cam is already hardened properly, so stop worrying and go for a drive.
Pete

 

Who to trust...

I would trust the engine makers; the GM guy said historical stuff that we all know is correct. The Castrol rep clearly didn't know anything except "ask your oem maker." The GM guy IS the oem maker (or at least one of them).

Re one of the myths he mentioned: we were building performance engines beginning in the late 70s using Mobil One for initial fill/break-in and from then on. It's the only oil we used unless a customer specifically stated he wanted something else. THe engines broke in perfectly and the Mobile One was worth 5-10 HP on the dyno over dino oil of the same weight. But we still hear that crapola about syns can't be used for break-in.

So in my mind the issue is as "over" as the "if you put a battery on a concrete floor it will discharge" myth. Yeah, that one WAS true once, as well...in 1915.

 

Don't confuse me with facts!, I've got my mind made up!. LA LA LA LA LA LA LA (fingers in ears)



(not directed at anyone)

 

I don't have any experience with over head cam motorcycle engines but I have had cam failures on 2V Ferrari motors that were blamed by the cam grinder on ZDDP.

There comments were ... "We run that grind on Chevy's on Porsche's all the time". The difference with a Ferrari is the size of the base circle. Because the base circle is small it proportionally shrinks the features on the entire lobe. What this does is make a "mild grind" put pressure on the lobes and tappets like a more agressive grind ... then add a truly agressive grind and the pressure is exponential.

Add the fact there's no rocker arm ratio to increase lift you can see why the shape of the cam ends up waaaay different then it does for a Porsche or Chevy.

cheers

 

"cam failures on 2V Ferrari motors that were blamed by the cam grinder on ZDDP"

Well, just like any oil argument, I guess this could go on forever.

However, Camshafts need proper break in and failing to do so will ruin one almost immediately regardless of what kind of oil you put in. Call me cynical but I have to wonder if the problems you experienced was the cam grinder's faulty cam material or faulty break-in process. It's a lot easier to blame the oil...

Back in the "old" days, with allegedly plenty of ZDP in oil, people still managed to regularly ruin camshafts by improper break in. It's really nothing new in that regard.

 

I could show you pics of the shims I pulled out at 100 hours. There was nothing wrong with them.

These cams had very pointed lobes ... you ever ran a cam with a lobe that has about -.015"-.03" nose radius? It looked wrong and because I am not a cam expert I didn't know the implications ... now I do ... cam engineers refer to it as "the minimum radius of curvature". That's how the cam looked with .406" lift and .242 duration ... not very aggressive compared to a Chevy. You go any more duration than that with that lift you go off the shim with the lobe. There's so much more going on ... comparing one of these motors to a typical flat tappet engine is a bit apples and oranges ... maybe? ... if there so similar everyone would be rebuilding them cheap but from what I see even experienced guys are apprehensive about diving in.

A motorcyle engine would be a good comparison because they are constrained with the overhead cams/base circle thing, unlike the single overhead cam Porsche and push rod American muscle. I posted a pic of the new Porsche cams which are double overhead cam without rocker arms ... they made the base circle massive. That same grind on our cams would have no nose radius at all.

Just sharing my personal experience because there is so much misinformation out there.

cheers

 

BTW ... the cam grinder will not grind that profile on a Ferrari cam anymore ... I luv doing R&D but I should've got the credit for that one . They were only willing to do .390" lift next time and I still haven't installed those cams. The first batch failed at 180 hrs ... 80 hrs after I inspected everything. I put in the stock cams after that and am now over 700 hours on the same motor ... maybe I broke them in properly .. oh yeah ... they had 100,000 miles on them so I guess they were pretty broke in .



cheers