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Best Engine oil for refurbed 3.0

Neun 11

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Have a refreshed 3.0 undergoing run - in atm. Now, some use different Engine oil on run - in, then change after to a different grade { perhaps  } 

My question, what is the best, or adequate oil to run, not only in a 3.0, but a refreshed engine? Penrite HR ? or HPR 30 gets mentioned now and then, due to the Zinc content. Do other compatible brands have a zinc content also? 

Thanks in advance.

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Have a refreshed 3.0 undergoing run - in atm. Now, some use different Engine oil on run - in, then change after to a different grade { perhaps  } 
My question, what is the best, or adequate oil to run, not only in a 3.0, but a refreshed engine? Penrite HR ? or HPR 30 gets mentioned now and then, due to the Zinc content. Do other compatible brands have a zinc content also? 
Thanks in advance.
Curious. Did you re-use the pistons and barrels, and put new rings in?

Sent from my LG-H815 using Tapatalk

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I know Penrite have a Running In Oil as well. Full disclosure, that they are helping out my builds, but I was talking to them the other day, and apparently the VW blend is actually a further developed version of Porsche's own stuff. HPR 30 is good, but according to them the VW/Aircooled blend is a bit better for our aircooled engines.


....waiting for the flaming to come....  :Sweating:

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The smart thing to do is to use whatever the engine builder recommends.  That way there is one less "get out clause" for the builder in the event that his handiwork is less than perfect and you need repairs done under warranty.


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1 hour ago, MFX said:

I know Penrite have a Running In Oil as well. Full disclosure, that they are helping out my builds, but I was talking to them the other day, and apparently the VW blend is actually a further developed version of Porsche's own stuff. HPR 30 is good, but according to them the VW/Aircooled blend is a bit better for our aircooled engines.


....waiting for the flaming to come....  :Sweating:

Penrite rep told me the same thing. I've used their oil in every car and bike I've owned 

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Apparently this oil is the go from what I was told by a previous owner of a air cooled race car that is gracing my garage. He insisted that this was the only oil to use, hence why is came with the car. 

The car has done plenty of track days and still going strong so I’m pretty confident it’s good stuff.



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2 hours ago, Neun 11 said:

Have a refreshed 3.0 undergoing run - in atm. Now, some use different Engine oil on run - in, then change after to a different grade { perhaps  } 

My question, what is the best, or adequate oil to run, not only in a 3.0, but a refreshed engine? Penrite HR ? or HPR 30 gets mentioned now and then, due to the Zinc content. Do other compatible brands have a zinc content also? 

Thanks in advance.

The best - but most expensive is mobil1 HD (Harley Davidson).

For the early K's in your motor after Run-In, just use the VW Penrite but change it a few times.

Good idea to look up what member, ' Buchanan Automotive ' has written on oil for A/C motors These 3.0s are old school engineering & what he says makes sense.

Remember that oil is probably the cheapest cost of motoring.

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59 minutes ago, Fraz said:

Apparently this oil is the go from what I was told by a previous owner of a air cooled race car that is gracing my garage. He insisted that this was the only oil to use, hence why is came with the car. 

The car has done plenty of track days and still going strong so I’m pretty confident it’s good stuff.



I don't see any mention of zinc content, and I think that may be a bit light for older A/C engines?

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43 minutes ago, Fraz said:

Apparently this oil is the go from what I was told by a previous owner....... He insisted that this was the only oil to use.....


12 minutes ago, Zelrik911 said:

The best - but most expensive is mobil1 HD (Harley Davidson).

How can you guys be so sure?

"Only one to use" and the "best" are pretty big statements.  Is there any data to back these statements up?


Also, are your recommendations suitable for the original enquiry about a newly rebuilt engine where the big concern is having the piston rings seat before the bores glaze and the broadly accepted wisdom with professional engine builders is to avoid synthetics like Mobil 1 V- Twin motorcycle oil during this very crucial phase.  My observation is that the professional builders who frequent Pelican Forum seem to be split three ways with the following preferences:  straight SAE30 such as that readily available from Valvoline, Joe Gibbs Break In Oil which the Penrite Run In oil would be our readily available equivalent and the good old mixed fleet HDEO's like Caltex Delo 400 15w40.  

Once the engine is broken in they then seem adopt whatever they're either comfortable with or have some sort of commercial agreement with and the only common themes being the viscosity matches Porsche's recommendations for whatever ambient temperature the car is expected to driven in and ZDDP being around 1200ppm. But even Porsche themselves don't strictly abide with this with the two oils they sell for air cools so no wonder there isn't a definitive answer.

Sure, use whatever you like but to say there is only one "best" oil cannot be factually substantiated and is in the realm of voodoo and witchcraft.

I suspect its all not as critical as we like to think it is. 

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You can always pop in some period additive 



Or this page is a gem  http://www.repairfaq.org/filipg/AUTO/F_Slick_502.html   see below

9. Detergents And Solvents

Many of the older, better-known oil treatments on the market do not make claims nearly so lavish as the new upstarts. Old standbys like Bardahl, Rislone and Marvel Mystery Oil, instead offer things like "quieter lifters," "reduced oil burning" and a "cleaner engine."

Most of these products are made up of solvents and detergents designed to dissolve sludge and carbon deposits inside your engine so they can be flushed or burned out. Wynn's Friction Proofing Oil, for example, is 83 percent kerosene. Other brands use naphthalene, xylene, acetone and isopropanol. Usually, these ingredients will be found in a base of standard mineral oil.

In general, these products are designed to do just the opposite of what the PTFE and zinc phosphate additives claim to do. Instead of leaving behind a "coating" or a "plating" on your engine surfaces, they are designed to strip away such things.

All of these products will strip sludge and deposits out and clean up your engine, particularly if it is an older, abused one. The problem is, unless you have some way of determining just how much is needed to remove your deposits without going any further, such solvents also can strip away the boundary lubrication layer provided by your oil. Overuse of solvents is an easy trap to fall into, and one which can promote harmful metal-to-metal contact within your engine.

As a general rule of thumb these products had their place and were at least moderately useful on older automobile and motorcycle engines of the Fifties and Sixties, but are basically unneeded on the more efficient engine designs of the past two decades.


10. The Infamous "No Oil" Demo

At at least three major motorcycle rallies this past year, we have witnessed live demonstrations put on to demonstrate the effectiveness of certain oil additives. The demonstrators would have a bench-mounted engine which they would fill with oil and a prescribed dose of their "miracle additive." After running the engine for a while they would stop it, drain out the oil and start it up again. Instant magic! The engine would run perfectly well for hours on end, seemingly proving the effectiveness of the additive which had supposedly "coated" the inside of the engine so well it didn't even need the oil to run. In one case, we saw this done with an actual motorcycle, which would be rid den around the parking lot after having its oil drained. A pretty convincing demonstration - until you know the facts.

Since some of these demonstrations were conducted using Briggs and Stratton engines, the Briggs and Stratton Company itself decided to run a similar, but somewhat more scientific, experiment. Taking two brand-new, identical engines straight off their assembly line, they set them up for bench-testing. The only difference was that one had the special additive included with its oil and the other did not. Both were operated for 20 hours before being shut down and having the oil drained from them. Then both were started up again and allowed to run for another 20 straight hours. Neither engine seemed to have any problem performing this "minor miracle."

After the second 20-hour run, both engines were completely torn down and inspected by the company's engineers. What they found was that both engines suffered from scored crankpin bearings, but the engine treated with the additive also suffered from heavy cylinder bore damage that was not evident on the untreated engine.

This points out once again the inherent problem with particulate oil additives: They can cause oil starvation. This is particularly true in the area of piston rings, where there is a critical need for adequate oil flow. In practically all of the reports and studies on oil additives, and particularly those involving suspended solids like PTFE, this has been reported as a major area of engine damage.


11. The Racing Perspective

Among the most convincing testimonials in favor of oil additives are those that come from professional racers or racing teams. As noted previously, some of the oil additive products actually are capable of producing less engine friction, better gas mileage and higher horsepower out put. In the world of professional racing, the split-second advantage that might be gained from using such a product could be the difference between victory and defeat.

Virtually all of the downside or detrimental effects attached to these products are related to extended, long-term usage. For short-life, high-revving, ultra-high performance engines designed to last no longer than one racing season (or in some cases, one single race), the long-term effects of oil additives need not even be considered.

Racers also use special high-adhesion tires that give much better traction and control than our normal street tires, but you certainly wouldn't want to go touring on them, since they're designed to wear out in several hundred (or less) miles. Just because certain oil additives may be beneficial in a competitive context is no reason to believe they would be equally beneficial in a touring context.


12. The Best of The Worst

Not all engine oil additives are as potentially harmful as some of those we have described here. However, the best that can be said of those that have not proved to be harmful is that they haven't been proved to offer any real benefits, either. In some cases, introducing an additive with a compatible package of components to your oil in the right proportion and at the right time can conceivably extend the life of your oil. However, in every case we have studied it proves out that it would actually have been cheaper to simply change the engine oil instead.

In addition, recent new evidence has come to light that makes using almost any additive a game of Russian Roulette. Since the additive distributors do not list the ingredients contained within their products, you never know for sure just what you are putting in your engine.

Recent tests have shown that even some of the most inoffensive additives contain products which, though harmless in their initial state, convert to hydrofluoric acid when exposed to the temperatures inside a firing cylinder. This acid is formed as part of the exhaust gases, and though it is instantly expelled from your engine and seems to do it no harm, the gases collect inside your exhaust system and eat away at your mufflers from the inside out.


13. Whatever The Market Will Bear

The pricing of oil additives seems to follow no particular pattern whatsoever. Even among those products that seem to be almost identical, chemically, retail prices covered an extremely wide range. For example:


  • One 32-ounce bottle of Slick 50 (with PTFE) cost us $29.95 at a discount house that listed the retail price as $59.95, while a 32-ounce bottle of T-Plus (which claims to carry twice as much PTFE as theSlick 50) cost us only $15.88.
  • A 32-ounce bottle of STP Engine Treatment (containing what they call XEP2), which they claim they can prove "outperforms leading PTFE engine treatments," cost us $17.97. Yet a can of K Mart Super Oil Treatment, which listed the same zinc-derivative ingredient as that listed for the XEP2, cost us a paltry $2.67.

Industry experts estimate that the actual cost of producing most oil additives is from one-tenth to one-twentieth of the asking retail price. Certainly no additive manufacturer has come forward with any exotic, high-cost ingredient or list of ingredients to dispute this claim. As an interesting note along with this, back before there was so much competition in the field to drive prices down, Petrolon (Slick 50) was selling their PTFE products for as much as $400 per treatment! The words "buyer beware" seem to take on very real significance when talking about oil additives.


14. The Psychological Placebo

You have to wonder, with the volume of evidence accumulating against oil additives, why so many of us still buy them. That's the million-dollar question, and it's just as difficult to answer as why so many of us smoke cigarettes, drink hard liquor or engage in any other number of questionable activities. We know they aren't good for us - but we go ahead and do them anyway.

Part of the answer may lie in what some psychiatrists call the "psychological placebo effect." Simply put, that means that many of us hunger for that peace of mind that comes with believing we have purchased the absolute best or most protection we can possibly get.

Even better, there's that wonderfully smug feeling that comes with thinking we might be a step ahead of the pack, possessing knowledge of something just a bit better than everyone else.

Then again, perhaps it comes from an ancient, deep-seated need we all seem to have to believe in magic. There has never been any shortage of unscrupulous types ready to cash in on our willingness to believe that there's some magical mystery potion we can buy to help us lose weight, grow hair, attract the opposite sex or make our engines run longer and better. I doubt that there's a one of us who hasn't fallen for one of these at least once in our lifetimes. We just want it to be true so bad that we can't help ourselves.


15. Testimonial Hype vs. Scientific Analysis

In general, most producers of oil additives rely on personal "testimonials" to advertise and promote their products. A typical print advertisement will be one or more letters from a satisfied customer stating something like, "1 have used Brand X in my engine for 2 years and 50,000 miles and it runs smoother and gets better gas mileage than ever before. I love this product and would recommend it to anyone."

Such evidence is referred to as "anecdotal" and is most commonly used to pro mote such things as miracle weight loss diets and astrology.

Whenever I see one of these ads I am reminded of a stunt played out several years ago by Allen Funt of "Candid Camera" that clearly demonstrated the side of human nature that makes such advertising possible.

With cameras in full view, fake "product demonstrators" would offer people passing through a grocery store the opportunity to taste-test a "new soft drink." What the victims didn't know was that they were being given a horrendous concoction of castor oil, garlic juice, tabasco sauce and several other foul-tasting ingredients. After taking a nice, big swallow, as instructed by the demonstrators, the unwitting victims provided huge laughs for the audience by desperately trying to conceal their anguish and disgust. Some literally turned away from the cameras and spit the offending potion on the floor.

The fascinating part came when about one out of four of the victims would actually turn back to the cameras and proclaim the new drink was "Great" or "Unique" or, in several cases, "One of the best things I've ever tasted!" Go figure.

The point is, compiling "personal testimonials" for a product is one of the easiest things an advertising company can do - and one of the safest, too. You see, as long as they are only expressing some one else's personal opinion, they don't have to prove a thing! It's just an opinion, and needs no basis in fact whatsoever.

On the other hand, there has been documented, careful scientific analysis done on numerous oil additives by accredited institutions and researchers.

For example:


  • Avco Lycoming, a major manufacturer of aircraft engines, states, "We have tried every additive we could find on the market, and they are all worthless."
  • Briggs and Stratton, renowned builders of some of the most durable engines in the world, says in their report on engine oil additives, "They do not appear to offer any benefits."
  • North Dakota State University conducted tests on oil additives and said in their report, "The theory sounds good - the only problem is that the products simply don't work."
  • And finally, Ed Hackett, chemist at the University of Nevada Desert Research Center, says, "Oil additives should not be used. The oil companies have gone to great lengths to develop an additive pack age that meets the vehicle's requirements. If you add anything to this oil you may upset the balance and prevent the oil from performing to specification."

Petrolon, Inc., of Houston, Texas, makers of Petrolon and producers of at least a dozen other lubrication products containing PTFE, including Slick 50 and Slick 30 Motorcycle Formula, claim that, "Multiple tests by independent laboratories have shown that when properly applied to an automotive engine, Slick 50 Engine Formula reduces wear on engine parts. Test results have shown that Slick 50 treated engines sustained 50 percent less wear than test engines run with premium motor oil alone."

Sounds pretty convincing, doesn't it?

The problem is, Petrolon and the other oil additive companies that claim "scientific evidence" from "independent laboratories," all refuse to identify the laboratories that conducted the tests or the criteria under which the tests were conducted. They claim they are "contractually bound" by the laboratories to not reveal their identities.

In addition, the claim of "50 percent less wear" has never been proven on anything approaching a long-term basis. Typical examples used to support the additive makers' claims involve engines run from 100 to 200 hours after treatment, during which time the amount of wear particles in the oil decreased. While this has proven to be true in some cases, it has also been proven that after 400 to 500 hours of running the test engines invariably reverted to producing just as many wear particles as before treatment, and in some cases, even more.

No matter what the additive makers would like you to believe, nothing has been proven to stop normal engine wear.

You will note that all of the research facilities quoted in this article are clearly identified. They have no problem with making their findings public. You will also note that virtually all of their findings about oil additives are negative. That's not because we wanted to give a biased report against oil additives - it's because we couldn't find a single laboratory, engine manufacturer or independent research facility who would make a public claim, with their name attached to it, that any of the additives were actually beneficial to an engine. The conclusion seems inescapable.

As a final note on advertising hype versus the real world, we saw a television ad the other night for Slick 50 oil additive. The ad encouraged people to buy their product on the basis of the fact that, "Over 14 million Americans have tried Slick 50!" Great. We're sure you could just as easily say, "Over 14 million Americans have smoked cigarettes!"-but is that really any reason for you to try it? Of course not, because you've seen the scientific evidence of the harm it can do. The exact same principle applies here.


16. In Conclusion

The major oil companies are some of the richest, most powerful and aggressive corporations in world. They own multi-million dollar research facilities manned by some of the best chemical engineers money can hire. It is probably safe to say that any one of them has the capabilities and resources at hand in marketing, distribution, advertising, research and product development equal to 20 times that of any of the independent additive companies. It therefore stands to reason that if any of these additive products were actually capable of improving the capabilities of engine lubricants, the major oil companies would have been able to determine that and to find some way to cash in on it.

Yet of all the oil additives we found, none carried the name or endorsement of any of the major oil producers.

In addition, all of the major vehicle and engine manufacturers spend millions of dollars each year trying to increase the longevity of their products, and millions more paying off warranty claims when their products fail. Again, it only stands to reason that if they thought any of these additives would increase the life or improve the performance of their engines, they would be actively using and selling them - or at least endorsing their use.

Instead, many of them advise against the use of these additives and, in some cases, threaten to void their warranty coverage if such things are found to be used in their products.

In any story of this nature, absolute "facts" are virtually impossible to come by. Opinions abound. Evidence that points one direction or the other is avail able, but has to be carefully ferreted out, and is not always totally reliable or completely verifiable.

In this environment, conclusions reached by known, knowledgeable experts in the field must be given a certain amount of weight. Conclusions reached by unknown, unidentifiable sources must be discounted almost totally. That which is left must be weighed, one side against the other, in an attempt to reach a "reasonable" conclusion.

In the case of oil additives, there is a considerable volume of evidence against their effectiveness. This evidence comes from well-known and identifiable expert sources, including independent research laboratories, state universities, major engine manufacturers, and even NASA.

Against this rather formidable barrage of scientific research, additive makers offer not much more than their own claims of effectiveness, plus questionable and totally unscientific personal testimonials. Though the purveyors of these products state they have studies from other independent laboratories supporting their claims, they refuse to identify the labs or provide copies of the research. The only test results they will share are those from their own testing departments, which must, by their very nature, be taken with a rather large grain of salt.


17. Sidebar: Synthetic Oils

Whenever we talk about oil additives, the subject of synthetic oils inevitably crops up. Actually, the tow subjects have very little to do with each other, but since many riders seem to equate additives and synthetics together in their minds, we will take a few lines just to clear the air.

Synthetic oils were originally developed for use in gas turbine engines. In most cases they are capable of maintaining their viscosity for longer periods of use and under much greater temperatures and pressures than petroleum products. Commons synthetics used for engine lubrication today are Polyalphaolefin (like Mobil 1) or Dibasic Organic Esters (like AMSOIL). They are fully compatible with conventional oils and can be mixed, providing their ratings match.

Probably the best situation is a blend of synthetics and mineral oils, such as Golden Spectro and AGIP Sint 2000. These products seem to offer the best of both worlds in protection and extended service life. They may cost considerably more than standard petroleum products, but they also can be used for much longer periods between oil changes without losing their protective capabilities.

Synthetics and synthetic blends offer a wider range of protection than standard petroleum products. However, it should be noted that this extended range of protection reaches into an area of temperatures and pressures virtually impossible to attain inside most motorcycle engines and transmissions. In other words, if you use them, you are buying a sort of "overkill protection." It's certainly not going to hurt anything - it's just unnecessary. That is, unless it makes you feel better knowing the extra protection is on board, in which case the added expense may be well justified.

As a basic rule of thumb, using the standard engine oil recommended by your bike's manufacturer and changing it about every 3000 miles will afford you all the protection you'll ever need. But if you feel better knowing you have more protection than you need or, if you like the extended service-life feature, there's certainly nothing wrong with using a premium grade synthetic blend lubricant.

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7 hours ago, Stew F said:

Curious. Did you re-use the pistons and barrels, and put new rings in?

Sent from my LG-H815 using Tapatalk

 Stew  F , yes, re-used Pistons, / rings, refurbished and now have been ceramic coated. New valves, Valves Guides etc. 


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1 hour ago, Neun 11 said:

re-used Pistons, / rings, refurbished and now have been ceramic coated. New valves, Valves Guides etc. 

A good 3.0 SC engine is great classic motor, so enjoy your rebuild.

Another tip is that "Porsche has a history of recommending inappropriate oils for their older cars"  so be careful. 

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The below  is a copy of what I posted a few months ago , in regards to the very deep last century  Porsche road engines including the air/oil cooled 911 engine/s , it gives an insight into why a decent quality 20w-50 engine oil for our climate is important for long life for these last century Porsche engines in regards to two main areas 

A ) Oil Film Strength , meaning the ability to keep metal parts away from each other where there is no oil pressure ( lots of places where this is important )

B ) Sufficient oil pressure at high RPM  to protect ( give enough oil pressure ) to the 911 con-rod journals no 2 & 5 , because the 911 engine like ( ALL ) road engines have the basic flaw of having a radial oil pressure feed entering the crankshaft which as the crankshaft spins faster & faster the centrifugal forces reduces the oil pressure trying to even get into the crankshaft let alone to the center of the crankshaft to feed the con- rod bearings with sufficient oil pressure as opposed to a proper race engine with axial feed crankshaft ( like the 917 engine etc ) which is not effected by the high RPM of the crankshaft

Its all basic physics



2017 , big year at Buchanan Automotive , we have never ever put out so much work & on the bigger jobs , the Ripple Effect is still a significant cause 

Ripple Effect ? ,what ripple effect I hear you ask 
Answer = Very Simple Physics with incredible damaging effects on last century Porsche engines in our climate  , or just about any climate for that matter when using completely stupid  Low Viscosity,  Low Oil Film Strength  engine oils( like the stupid use of a this century 5w-40 viscosity) in last century Porsche engines in our climate, its not as bad as it was 10-20 years ago , but its still bad enough & boy oh boy its costly to the owners & its Completely Avoidable & worst still , the use of these so called synthetic Low Viscosity , Low Oil Film Strength 5w-40 & 10W-40 engine oils has had far reaching consequences over the decades , meaning these last century Porsche engines only needed to be on a Low Oil Film strength engine oil for as little as 10,000 - 20,000 Kms to create accelerated internal engine wear & if that engine ( later ) switched back to a decent Oil Film strength 15w-50 or a 20w-50 the internal wear was slowed or even stopped( relative to how fast the wear was ) at that point in time 
During 2017 we had multiple ( new to us ) 944 / 951 / 944S2 / 968 Porsche cars where we were preparing for the new owner to do a bit of club track driving & naturally with these cars typically already traveled 200,000 Kms + &  some 23 to 35 years old already , we even had a very nice 968 that was low recorded Kms , but with Shocking amount of Valve Guide Wear & excessive con rod bearing wear   , the silliest thing would be to take one of these old cars to the track without some basic preparation , because engine life on a race track with a human behind the steering wheel & the "Red Mist" appears ( it usually does  ), engines that are worn / fatigued just go bang & its mostly avoidable  & naturally ,preparation is not just the engine / engine bay ( fuel /oil /coolant hoses) , but steering & brakes + ball joints checking & or replace 
Note } Red Mist is a saying when a driver gets way too excited on a track & goes all out , even though the driver had no intention at all in doing that in the first place (Male humans in cars Verses other Male humans in their cars = Interesting Mix of engines going BANG with old worn engines )
Three Main Areas of concern that we look / rectify before letting out onto the track , particularly if the previous service records show anything other that 15w-50 or 20w-50 engine oils being used previously over the decades , this applies to all 944 variants & naturally the 928 series ( two 944 engines combined ), but generally only if they are going to the track to be punished 
Area of Concern 1 }
Twin Cam 944S /  944S2 / 968  ( in many ways they are basically half a 928S/32v / 928S4 / GT/GTS engine ) , yes I know there are lots of small differences , but in basic terms they a pretty much half a 928 quad cam engine & like what we see on the 928 Quad cam engines .       The thin single row timing chain between the two cams , this is on the 944S , 944S2 , 968 & the quad cam 928 series ,  these tiny ,thin single row chains( one per head ) are quite suitable for what there are designed to do & thats simply to drive the Inlet cam by the Exhaust cam & naturally there is going to be a hydraulic ( Oil Pressure Fed) tensioner with its nylon pads putting sufficient out -ward tension on the chain , now this is where the problems start if the engine oil pressure is too low when the oil is HOT & no I am not talking about the track at the moment at all , I am talking about the years of driving , might be to & from work ( normal street deriving ) in the normal thick / heavy Sydney / Melb / Brisbane traffic snarls , engine oil hot & getting hotter ( all very normal ) except for one small detail , this poor 944 twin cam or 928 quad cam engine is on a Low Viscosity , low Oil Film Strength 5w-40 or 10w-40 so called synthetic engine oil during these few years or so , made even worst still in the simple fact that the very very low Oil Pressure at idle has to supply Oil Pressure to the timing chain tensioners at the TOP of the engine , the oil pressure that is already too low is even lower at the top 
So what is the concern  I hear you ask ?
Answer =   The Death Rattle , the engine oil viscosity is so low( 5w-40 is a good contender here ) for the conditions ( mentioned above ) it means that at that normal idle speed ( in traffic ) the oil pressure at the hydraulic tensioner/s is so low the tensioner is no longer tensioning & the poor little timing chain is whipping around on and leading to the cam sprockets on the cams , this death rattle also damages the nylon tensioner guides ( shortens their lives remarkably ) and naturally beat the hell out of this thin single row chain because the engine oil is Low Viscosity & Low Oil Film Strength the metal timing chain is able to cut through the oil film( much lower oil film strength ) and bite into the cam chain "CAST" metal sprockets , causing excessive wear to them , which in turn causes more slack to occur ( metal missing from the teeth )& its a recipe for breakage & break they do and its very nasty ( bent valves , hydraulic tensioner ripped from the head & smashes  through the magnesium twin cam cam-cover ( what an expensive mess )& completely avoidable 
Note 1 }  The" twin cam " camshafts chain sprockets are situated in the middle of the camshaft & are not replaceable separately , they are cast & machined finished with the camshaft( all one piece) , its quite a trick centre drive setup , but expensive if worn & they basically do not wear "IF" that are given every possible chance to survive , meaning good OIL PRESSURE hot at idle = 15w-50 or 20w-50 = ( correct chain tension at idle )  & sufficient Oil Film Strength Engine Oil to keep the chain from biting through the oil film & making metal to metal contact 
Both Sean & I have heard the death rattle on many occasions ( engine oil hot at idle speed ) , but never when the twin cam 944s/S2/968 or quad cam 928  has been on sufficient oil viscosity for our Australian conditions = 15w-50 or 20w-50 and the basic condition of the timing chains, nylon guides & hydraulic tensioner is in reasonable to good condition
We have lost count how many " New to Us " 928 Quad Cam ( 86-95) , 944 Twin Cam ( 87-95) , 964 911 , 993 911 that had dropped by our workshop ( Mid Summer/hot day ) engine Oil Warning Pressure light Glowing RED , Oil Pressure gauge reading virtually nothing , engine making interestingly bad noises (loose timing chain noises, all at idle ) and all these were on a 5w-40 & even some 10w-40 engine oil viscosities , drained this incompatible oil out of them , changed the oil filter & refilled with 20w-50 & noises dramatically reduced or completely gone & oil pressure warning no longer glowing at idle with that oil temp , but then again is says to use 20w-50 in the owners manual that was printed by Porsche when these cars were new , so its not rocket science 
On a  944S , 944 S2 or a 968 ( Twin Cam Engines ) we routinely remove the cams about every130,000 - 150,000 kms & replace the nylon tens pads ( genuine Porsche ) and the timing chain ( Street Car ) but on a more dedicated track & some road driving 944 , then we replace them more often ( cheap insurance ) , removal of the two cams on the 944 series ( 87-95) is much much easier than on a 928 quad cam , access is far better 
Area of Concern 2 }
Valve Guide wear , like on a air /oil cooled 911 engine excessive valve guide wear is always a great concern if the said engine is taken to the track & flogged , there is a reasonable chance the engine could drop a valve head , thats because the heat from the valve head is not getting dispersed through the valve guide & into the cylinder head , instead the excessive valve guide wear is trapping the heat in the valve head just enough that at high RPM it will fail & the valve head will just fall off & into the combustion chamber ( Good Night Nurse ). Naturally the bigger the valve head the more it literally weighs & the valve springs closing force is very high & these single cam ( 2 valve heads ) are slightly more prone to it , so be careful with old Porsche engines going to the track for the first time with unknown valve guide wear ( it can catch you out easily )
As I briefly mentioned above , we had a very nice example of a 968 ( manual trans ) at our workshop recently & during repairs & tests , we had the cams out & I removed 4 or 5 of the 8 exhaust valve hydraulic lifters & I had made years ago a special tool were I can easily do a cursory valve guide wear check ( while the cams were off doing the timing chain and slipper guides )  & I was dumbfounded by the amount of( valve stem side ways movement ) valve guide wear , I even took out some of the inlet valve hydraulic lifters & even found one or two inlet valve guides with way way way too much wear ,we removed the cylinder head this 1992  968 engine ( still had its original wax fibre composite graphite head gasket )which was rotted away( good to get rid of that and install a metal custom head gasket ) , but when we had the 16 valves out , the valve guide wear was out of this world ( way way war too excessive for there Kms travelled ) long story to this car , but in a nut shell the valve guides were worn by the previous use of a low viscosity , low oil film strength engine oil , very very common 15 to 20 years ago to use these oils in these cars , but it was all the rage then ( Emperor's New Clothes ), even though the correct answer was in the owners manual printed by Porsche 
Remember  }  There is NO Oil Pressure at the valve guides , its just very very minor splash( more of a weep at best ) & in fact the valve stem seal keeps most of it off the valve guide/valve stem , so the valve stem & valve guide relies on High Oil Film Strength engine oil ( Very Simple Physics ) , so a Low Viscosity , Low Oil Film Strength so called synthetic engine  oil can easily turn into high wear for mechanical items in these engines that get No Oil Pressure 
Basics Physics Time }
A this century low viscosity engine oil , say a normal street emission compliant 5w-40  ( available to the public off the shelf ) is always going to be lower oil film strength than a last century 20w-50 that has good levels of WWII vintage ZDDP AW packages & then if you compare the same 5w-40 emission compliant engine oil up against a 25w-60 racing oil( we use on track prepared 944 etc )  , then the oil film strength difference is greater still 
Oil Pressure } the lower the Oil Viscosity the lower the oil pressure in the same test engine at the same oil temps , so in other words a 5w-40 will give ( Hot ) a lower oil pressure in the same last century Porsche engine than a 20w-50 engine oil ( same engine , same oil temp , same RPM Testing / reference points , Very Basic Physics )
Note 2 }   In a last century 944 engine ( all ) last century 928 engine ( all ) last century 911air/oil cooled engine ( all )  , here is the list of engine components that get NO ( NO ) Oil Pressure & must rely on Oil Film Strength 
A )   944 & 928 ( all )  tall wide pointy cam lobes striking at high speed against the flat hydraulic lifter face , and the lifter/s is held up with two big valve springs ( no valve bounce with this spring tension ), this is whats known as High Wiping Loads ( High Loaded Flat Tappet Design ) , meaning the force applied is wanting to just wipe the oil clean off the lifter face , if the pointy tall cam lobe/s break through the oil film its instant metal to metal , the oil film is the liquid bearing , naturally its this area that ZDDP pressure induced cross linking AW film forms & with the correct Oil Viscosity , from minus 10 deg cel to unlimited high ambient temps = 20w-50 the cams will survive & as mentioned there is No Oil Pressure here at all , just splash   
B )  911 Air/Oil cooled , rocker shafts to cam lobes , same deal , no oil pressure , just a spray of oil in the general direction & the Oil Film Strength has to be high , same goes for the rockers pivoting on their rocker shafts , the lubrication here ZERO  , oil film strength only 
C ) 944 twin cam , 928 quad cam , 911 air/oil cooled Timing Chains against their Timing Chain Sprockets , , lots of forward and back shockwaves in this area ( opening and closing valves causes the shock waves ) , No Oil Pressure here to protect from excessive metal to metal contact , just slash & Oil Film Strength 
D ) Alloy Pistons in their Alloy Cylinder Bores , be it 944 , 928 , 911 , No Oil Pressure here , just splash & Oil Film Strength 
E ) Piston small end bearing ( top of con-rod inside piston ) , just splash feed & Oil Film Strength 
F ) Piston Rings against cylinders & inside the piston lands , just splash feed & Oil Film Strength 
G ) Piston gudgeon pin ( Wrist Pin in USA speak ) moves inside the alloy piston ( 944 , 928 , 911 ) and must be lubricated , no oil pressure , just a bit of splash feed & Oil Film Strength 
H )  Crankshaft Thrust Bearing , this stops the crankshaft from moving forward or back in operation & with a manual transmission 944 , 928 , 911 the load from the clutch arm pushing or pulling ( depending on the design ) will transmit massive forces in one direction & if the thrust bearing is having to cope with low oil film strength engine oils there is always going to be issues with the thrust bearing 
Note 3 } The crankshaft thrust bearing has grooves / openings through which the engine oil escaping from the adjacent main bearing must must be let through at the same rate as the other engine main bearings , hence the openings / grooves in the working face of the thrust bearing , in my opinion there is no oil pressure at this thrust bearing surface , and it relies on Oil Film Strength , hence why we see ZERO thrust bearing wear on any last century Porsche if its been on a 20w-50 engine oil at all times , but on lesser oil film strength engine oils we see thrust bearing wear , meaning oils like 5w-40 & some 10w-40 etc in our Australian climate , but then again the answer has always been in the owners manual that came with these last century Porsche cars 
Note 4 } 928S/S4/GTS Auto Trans version / Front Flex Plate deflected & pushing the bowl shaped flywheel in constantly against the engine thrust bearing , in a nut shell we have seen many of these over the last 15 or so years that the "rear of T Tube" coupling has not been maintained & the single bolt holding it tight has stretched & with the twist of the shaft under acceleration ( shortens the shaft momentarily )& because the front coupling does not loosen as much , the shaft pulls out of the rear coupling and over time you end up with the front flex plate deflected , its not a lot of tension ( you can move the flex plate in with you thumb ) but its a constant inwards tension & with the engine thrust bearing having NO oil pressure to protect it , it has to rely on the Oil Film Strength to protect it & if the oil film strength is low , then bad luck for you , because the engine thrust bearing will wear out & the crankshaft will eventually grind through the thrust bearing & into the crankcase .
 BUT we have caught quite a few ( new to us 928S / S4 / GTS 928 Auto ) cars that we have done our T Tube reset & new coupling index bolts  & measure the axial play of the crank ( thrust bearing check measurement ) & the ones that are worn ( but not worn out ) we have noted / recored the wear measurement number for that particular 928 , change the engine oil & oil filter to a good quality 20w-50  & then a few years later we go back in to do a T Tube reset & re-measure the wear amount & we have never seen one yet that the wear amount has increased one bit , the wear has completely Stopped , thats because we switched back to a high oil film strength engine oil & looked after the T Tube ( very easy stuff if you know what you are doing )
Remember , the Oil Film Strength varies greatly between most 10w-40 , 5w-40 & even a few 15w-50 in different brands & even great differences between the same brand but different countries 
Area of Concern 3 } 
In a 944 / 944S / 944S2 / 951 / 968 ( all ) the con-rod bearing journal ( big end bearing ) that will starve of oil pressure at high sustained RPM with normal hot oil temperature with a Low Oil Viscosity ( classic example = 5w-40 ) is journal no 2 & when it starves its all over in a second or two , crankshaft is destroyed & often the con-rod lets go = good night to the engine crankcase & sometimes cylinder head as well ( piston smashes into it , because its now free from constraint )
In a 928, 928S , 928S4 , 928GT, 928GTS ( all ) its con-rod journals no 2 & 6 ( they are on the same crank journal ) and like on a 944 its all over in a few seconds when its at high sustained RPM with the engine oil at normal high temps , the first one we came across was Charles Falzon who destroyed his engine ( on the road ) No 2 & no 6 con-rod bearings staved of oil at high RPM on a famous brand so called synthetic 5w-40 , the so called synthetic side of things did sweet F---k all for that engine ( destroyed / turned to scrap in a second or two ) & since then we have seen a few more , always on a 5w-40 or even a 10w-40 
In a air / oil cooled last century 911 > 993 , they will destroy con-rod bearings 2 & 5 , not on the same journals , but in the middle of the crank , same outcome if on the wrong oil viscosity at high sustained  RPM & hot operational oil temps with a 5w-40 
But Why is it So ?  
Answer is quite simple }
The above engines are all road engines & all road engines in last century & this century for that matter have to be functional with BOTH ends of the crankshaft to be used in practical ways , meaning the rear of the crank will need a flywheel , so there is no possible way of doing the Porsche 917 engine thing of having the engine oil pressure feed coming in at that end of the crank( axial feed ) & at the front of the engine we have on road engines pulleys, with a massive bolt in the centre holding the pulleys on that drive fan belts / A/C belts / Power Steer belts etc etc etc , so there is NO possible way of getting engine oil pressure into the front of the crank ( axial feed )
So what are we left with with all of us playing around with ROAD ENGINES , we have to put up with RADIAL feed into the crankshaft to feed oil pressure to the critical con-rod bearings ( big end bearings ) 


Think about it for a few seconds and it becomes crystal clear ,radial feed on road engines ( 911 , 928 , 944 ) is perfectly fine for most road conditions even at high RPM momentarily , so long as you keep the oil pressure up HIGH ENOUGH to overcome the high spinning speed of the crankshaft throwing the engine oil out ( centrifugal force ) through the very hole the oil is trying to get in to feed the Con Rod bearings along the length crankshaft , its a terrible compromise , but works OK until the Oil Pressure is insufficient & when it is at high RPM , you do not get any warning , its all over in a second or two ( BANG )
Here are some notes written by Hans Mezger ( the designer of quite a few Porsche race engines including the famous 12 cylinder 917 engine }
Because the 911 air/oil cooled engine used for road and competition had Radial feed into the crankshaft to the  con-rod bearings , the Oil Pressure needed at 9,000RPM was 70 Lbs Sq " ( 5kp/cm/2)  MIN pressure at max racing oil temp
The 908 ( 8 cylinder ) 3.0L air/oil cooled race engine had Radial feed to the con-rod bearings , to overcome con-rod bearing issues in racing the crankshaft required at 9,000RPM was 100 Lbs Sq " ( 7 Kp/cm/2 ) Min oil pressure at Max racing oil temp ( Thats Massive Oil Pressure ) 
Hence why proper race engines like the 917, 12 cylinder engine had Axial feed & with axial feed there are NO centrifugal forces pushing away the oil trying to get into the crank , so with Axial feed the 917 engine only required at 10,300 RPM was 34Lbs Sq " ( 2.3 Kp/cm/2 ) Oil pressure 
So with these  last century Porsche road engines we play around with , remember none of them are race engines , yes you can take them to the track , but we need to know why they go BANG & try to avoid it , so obviously we can not turn these into radial feed crank designs ( not going to happen ) , but what we can do is what Porsche did with their 1960's road / race engines , you work with what you have and recognize you need to compensate for the loss of oil pressure going to the con rod bearings ( big ends ) as the crank spins faster & faster ( radial feed has to fight against centrifugal forces ) , its not perfect but we can work with it 
Using LOGIC , we know that the lower the oil viscosity , the lower the oil pressure , very single physics & as you can see , last century Porsche road engines need high oil pressure going into the crank & thats why over the last 11 years in the PCNSW we have never lost a single 944 , 944S , 944S2 , 951 , 968 engine that compete at the track ( Supersprints ) & we and our customers have won multiple Drivers Championships & Super Sprint  championships & Motorkhana Championships ,  so to let you into a secret we use at the track a Minimum Viscosity of 25w-60  Racing oil in all these 944 variants , two of these Porsche's ( 3.0L 951's on E85 ) put out just on 600 HP and they are all wet sump , no acusump & no dry sump & remember all these Porsche's are road & track cars , meaning they all drive to the track & drive home again , they are not dedicated race cars & remember the tracks we compete at do not have some of the very very long sweeping corners that exist at some tracks in other countries , so we can get away with no dry sump in our circumstances , the closets to that is the vary fast corner 1 at  Sydney Motor Sport Park , it is a very fast sweeping corner at high RPM , but we have no issues with it 
So remember , prepare a last century Porsche engine for the flogging if its going to the track & the beauty of the 944 engines ( like the 928 engines) , is we can remove the engine sump to change the sump gasket & at the same time remove the individual con-rod caps to check the condition & or replace the bearing shells & cap nuts ( all in the car ) , just like on an old Datsun 1600 or Ford escort , Fantastic Design 
The Above is MY OPINION in what I have experienced as a independent Porsche Specialist  working on Porsche sports cars 6 days a week  since 1977 (   getting on 41 years ) & the reason is I am sick & tired of seeing lovely last century Porsche engines being flogged at the track & even on the road on a way too thin this century engine oil & it all ends in tears ( Con Rod Bearings starvation mostly ) & another Porsche engine going to scrap metal ( lost forever ) , I just hope I can save a few last century Porsche engines from this stupid  avoidable destruction
And lastly , the above has NOTHING at all to do with this century Porsche engines , meaning Boxster , 996 , 997 etc etc etc ,I am ONLY talking about oil viscosity & Oil Film strength & Oil pressure issues to the 944 ( all ) , 928 ( all ) and air / oil cooled 911 ( all ) road going Porsche cars from deep last century from when 20w-50 engine oils were the norm 
Bruce Buchanan 
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I  relieved to see phrases like "basic physics" because most oil threads seem to be populated by self taught rocket scientists :D

They sometimes used tallow in the gearboxes/diffs of the Peking to Paris cars. Almost the century before the last one ;)
Problem now is you cant get tallow at Supercheap.

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6 minutes ago, Troubleshooter said:

Certified peta and vegan friendly?:ph34r:

In peking I think they used to just hack it off passing animals. Actually , I think they did that in the Aussie outback. Probably still do.

In the outback there is no politics so you can't really be politically correct...and there are no vegans out there ;)

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