Castrol Edge Sport 10W60
10-02-2009, 11:40 AM
#46
Administrator - "Tyson"
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The issue is new standards that drop the level to 800ppm or less. The old standard was 1200ppm. Some of the "boutique" oils have as much as 1700ppm.
You also need to think about how much PPM you are adding. If a quart of additives has 2,000ppm in a 1 liter bottle, split that across 10 quarts you are only increasing the ZDDP by 200ppm.
Just use an oil that has the level that makes you comfortable.
Race engines use straight W50 ,W60, W70 oil. This oil is different as it has no polymeric compounds in it to alter viscosity. It is made to offer the best performance only above 100degC. FYI Honda's famous motorcycle racing engine RC350 peaked at 22000 rpm (yes, 22 000) back in 1963 and used straight castor oil!!!
The wider the gap between the first and second number in multi-weight oils, the more viscosity additives are added. These break down over time / use / stress which is why most race engines are run on straight weight.
This is also why I will never us 5w-50 in any engine I care about.
10-02-2009, 12:14 PM
#47
Man of many SIGs
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All motor oils have ZDDP.
The issue is new standards that drop the level to 800ppm or less. The old standard was 1200ppm. Some of the "boutique" oils have as much as 1700ppm.
I've read mixed answers. Some claim the balance of ZDDP in the oil with other additives is very important meaning that simply adding additional ZDDP is only part of the solution.
Just use an oil that has the level that makes you comfortable..
The issue is new standards that drop the level to 800ppm or less. The old standard was 1200ppm. Some of the "boutique" oils have as much as 1700ppm.
I've read mixed answers. Some claim the balance of ZDDP in the oil with other additives is very important meaning that simply adding additional ZDDP is only part of the solution.
Just use an oil that has the level that makes you comfortable..
The wider the gap between the first and second number in multi-weight oils, the more viscosity additives are added. These break down over time / use / stress which is why most race engines are run on straight weight.
This is also why I will never us 5w-50 in any engine I care about.
This is also why I will never us 5w-50 in any engine I care about.
10-02-2009, 12:28 PM
#48
Administrator - "Tyson"
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Ironically Mobil 1 has a PDF on their website that lists them all. I'll try to find the link.
EDIT - found it:
http://www.mobiloil.com/USA-English/...duct_Guide.pdf
According to a local petroleum engineer that I spoke with, the additives are actually a polymer that curls into a spiral or straightens out depending on temperature. The old tech polymers suffered from something called shear. This meant that the polymer strings were chopped in half due to extreme forces being applied to them in tight clearances in the engines. He claims that this isn't a concern in modern multiviscosity oils due to a difference in polymer technology. Maybe Doug Hillary can comment on this further.
10-03-2009, 01:27 AM
#50
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For the record I'm using an 10W40 Synthetic and on a hot day in traffic the oil pressure will sit at 2BAR which I feel is too low. The car runs great otherwise and never runs hot. I am considering making a switch to a heavier oil but I'm on the fence. Threads like this can be helpful for those trying to learn and decide what to do.
10-03-2009, 03:31 AM
#51
Drifting
Hi Turbochad , in the case of the 928 and 944 engines that's not the case exactly , in regards to the 928 engine , the oil pressure relief valve opens at 8 bar (aprox 120 psi) , however the oil pressure gauge only goes to the max indicated pressure of 5 bar (75 psi aprox), which means you get a false impression when the engine oil is at 95 deg cel or more say on a warm to hot day and indicated oil pressure on the oil pressure gauge (dash instruments) reads just over 4 bar when reving it up to or near redline, which it will with a 10w-40 oil , you are in fact only creating 1/2 the possible oil pressure than can be produced , the 928 and 944 oil pressure gauges should read 0 - 10 bar , like they did on the 924 series.
I am not saying we need to keep it at or near 8 bar , just a bit more than 4 bar at high temps
Why is that important ?
Answer = there is a built in flaw in the 928 engine at high rpm(engine hot) the oil pressure at the bigend bearings is not the exact same pressure that is at the main bearings (lower at the big ends), and most importantly the big end bearing journals no 2 & 6 are lower pressure still , these are the two bearings at risk on a 928 (all variants)
And on the 944 series and 968 (all) its no 2 big end journal.
Now over the years we have lost count how many 928 (all types) 944 (all types) that we have seen loose their bottom end(read destroyed crank and worse) be it a bit of club sprinting on the track or in some cases on the road just giving the engine a workout , in every case these engines were on a too lower viscosity for that particular ambient temp/ situation / event , however if these same Porsche's were driven more sedately , i would suspect all would of been OK.
Now how many have we seen blow the bottom ends, no's 2 & 6 (928) , no 2 (944) that have been on a 20w-50 road or 25w-60 track oil vis that have good bigend bearings to start with
Answer = None .
So all we do is to consult the owners manual , Printed by Porsche for the relevant type , be it 928 , 944 , 951 etc etc and on the oil viscosity page , smack in the middle is the shaded look at me section and the first cab off the rank is a ambient temp range of minus ten deg cel (14 deg F)to unlimited high temp and the oil vis recommended is a 20w-50.
That happens to be from a 1994 year type 928GTS .
So by keeping the vis in with the recommended for the ambient temp range we have two things
A) completely stopped the bottom end failures (hot with big revs)
B) the vast majority of 20w-50 oils have decent ZDDP , this has not always been the case even with some 15w-50 ,particularly 10w-40 , 5w-40 oils sold to the public particularly between 1998- 2008 some had very low ZDDP and what was worse the oil companies would change (lower the ZDDP) without notice .
We have not found this to be the case with 20w-50 because this is very much a last century viscosity for last century cars (like the 928, air cooled 911 , 944 etc) and it (20w-50)did not have to comply to the stricter emission protocols regarding the lowering of ZDDP(for this century cars) and replacing it with the newer AW packages .
Important Note , if a 928 or a 944 already has worn bigend bearings (no knocking as yet but not far away)then switching to any viscosity oil higher will not help or stop it from going pop .
However if the bigends are in good condition , example the sump removed to replace an old sump gasket and at the same time the big end caps removed and checked (that's what we do ), and amazingly over the last few years we have found many 944 series and 928 series engines that have documented history of being on a much lower viscosity oil for the ambient temp range have had very noticeable wear on 2 & 6 (928) and 2 (944) where as the ones that have been on a 20w-50 (regular servicing) have had no wear .
So it would appear that that little bit more oil pressure actually saves the big end bearings that are at most risk .
This is what we see .
Regards
BB
I am not saying we need to keep it at or near 8 bar , just a bit more than 4 bar at high temps
Why is that important ?
Answer = there is a built in flaw in the 928 engine at high rpm(engine hot) the oil pressure at the bigend bearings is not the exact same pressure that is at the main bearings (lower at the big ends), and most importantly the big end bearing journals no 2 & 6 are lower pressure still , these are the two bearings at risk on a 928 (all variants)
And on the 944 series and 968 (all) its no 2 big end journal.
Now over the years we have lost count how many 928 (all types) 944 (all types) that we have seen loose their bottom end(read destroyed crank and worse) be it a bit of club sprinting on the track or in some cases on the road just giving the engine a workout , in every case these engines were on a too lower viscosity for that particular ambient temp/ situation / event , however if these same Porsche's were driven more sedately , i would suspect all would of been OK.
Now how many have we seen blow the bottom ends, no's 2 & 6 (928) , no 2 (944) that have been on a 20w-50 road or 25w-60 track oil vis that have good bigend bearings to start with
Answer = None .
So all we do is to consult the owners manual , Printed by Porsche for the relevant type , be it 928 , 944 , 951 etc etc and on the oil viscosity page , smack in the middle is the shaded look at me section and the first cab off the rank is a ambient temp range of minus ten deg cel (14 deg F)to unlimited high temp and the oil vis recommended is a 20w-50.
That happens to be from a 1994 year type 928GTS .
So by keeping the vis in with the recommended for the ambient temp range we have two things
A) completely stopped the bottom end failures (hot with big revs)
B) the vast majority of 20w-50 oils have decent ZDDP , this has not always been the case even with some 15w-50 ,particularly 10w-40 , 5w-40 oils sold to the public particularly between 1998- 2008 some had very low ZDDP and what was worse the oil companies would change (lower the ZDDP) without notice .
We have not found this to be the case with 20w-50 because this is very much a last century viscosity for last century cars (like the 928, air cooled 911 , 944 etc) and it (20w-50)did not have to comply to the stricter emission protocols regarding the lowering of ZDDP(for this century cars) and replacing it with the newer AW packages .
Important Note , if a 928 or a 944 already has worn bigend bearings (no knocking as yet but not far away)then switching to any viscosity oil higher will not help or stop it from going pop .
However if the bigends are in good condition , example the sump removed to replace an old sump gasket and at the same time the big end caps removed and checked (that's what we do ), and amazingly over the last few years we have found many 944 series and 928 series engines that have documented history of being on a much lower viscosity oil for the ambient temp range have had very noticeable wear on 2 & 6 (928) and 2 (944) where as the ones that have been on a 20w-50 (regular servicing) have had no wear .
So it would appear that that little bit more oil pressure actually saves the big end bearings that are at most risk .
This is what we see .
Regards
BB
10-03-2009, 05:21 PM
#52
Addict
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Hi Turbochad , in the case of the 928 and 944 engines that's not the case exactly , in regards to the 928 engine , the oil pressure relief valve opens at 8 bar (aprox 120 psi) , however the oil pressure gauge only goes to the max indicated pressure of 5 bar (75 psi aprox), which means you get a false impression when the engine oil is at 95 deg cel or more say on a warm to hot day and indicated oil pressure on the oil pressure gauge (dash instruments) reads just over 4 bar when reving it up to or near redline, which it will with a 10w-40 oil , you are in fact only creating 1/2 the possible oil pressure than can be produced , the 928 and 944 oil pressure gauges should read 0 - 10 bar , like they did on the 924 series.
I am not saying we need to keep it at or near 8 bar , just a bit more than 4 bar at high temps
Why is that important ?
Answer = there is a built in flaw in the 928 engine at high rpm(engine hot) the oil pressure at the bigend bearings is not the exact same pressure that is at the main bearings (lower at the big ends), and most importantly the big end bearing journals no 2 & 6 are lower pressure still , these are the two bearings at risk on a 928 (all variants).......
.....However if the bigends are in good condition , example the sump removed to replace an old sump gasket and at the same time the big end caps removed and checked (that's what we do ), and amazingly over the last few years we have found many 944 series and 928 series engines that have documented history of being on a much lower viscosity oil for the ambient temp range have had very noticeable wear on 2 & 6 (928) and 2 (944) where as the ones that have been on a 20w-50 (regular servicing) have had no wear .
So it would appear that that little bit more oil pressure actually saves the big end bearings that are at most risk .
This is what we see .
Regards
BB
I am not saying we need to keep it at or near 8 bar , just a bit more than 4 bar at high temps
Why is that important ?
Answer = there is a built in flaw in the 928 engine at high rpm(engine hot) the oil pressure at the bigend bearings is not the exact same pressure that is at the main bearings (lower at the big ends), and most importantly the big end bearing journals no 2 & 6 are lower pressure still , these are the two bearings at risk on a 928 (all variants).......
.....However if the bigends are in good condition , example the sump removed to replace an old sump gasket and at the same time the big end caps removed and checked (that's what we do ), and amazingly over the last few years we have found many 944 series and 928 series engines that have documented history of being on a much lower viscosity oil for the ambient temp range have had very noticeable wear on 2 & 6 (928) and 2 (944) where as the ones that have been on a 20w-50 (regular servicing) have had no wear .
So it would appear that that little bit more oil pressure actually saves the big end bearings that are at most risk .
This is what we see .
Regards
BB
10-04-2009, 12:07 AM
#53
Rennlist Member
Hi Turbochad , in the case of the 928 and 944 engines that's not the case exactly , in regards to the 928 engine , the oil pressure relief valve opens at 8 bar (aprox 120 psi) , however the oil pressure gauge only goes to the max indicated pressure of 5 bar (75 psi aprox), which means you get a false impression when the engine oil is at 95 deg cel or more say on a warm to hot day and indicated oil pressure on the oil pressure gauge (dash instruments) reads just over 4 bar when reving it up to or near redline, which it will with a 10w-40 oil , you are in fact only creating 1/2 the possible oil pressure than can be produced , the 928 and 944 oil pressure gauges should read 0 - 10 bar , like they did on the 924 series.
I am not saying we need to keep it at or near 8 bar , just a bit more than 4 bar at high temps
I am not saying we need to keep it at or near 8 bar , just a bit more than 4 bar at high temps
So I went out to the garage and opened the owner's manual (first time) and sure enough it reads as you say (20-50 for temps above 0c). When I read your response I had a hard time justifying in my mind 20-50 for a street 928. I do run old school 20-50 Kendal GT1 in my turbocharged karmann ghia, but I drag race it at 8000rpm shifts (runs low 12s on street tires). I don't do anything of the like in my 928. Porsche recommends 0-40 Mobil 1 as a standard use oil in its cars (which also has the higher Zink and Phos levels). I would think that for most users in most climates this would be fine. If you track your car I can see your point in stepping up up to a higher viscosity such as Mobil 1 5-50 as recommended by Porsche because of the increased oil temps and even higher zinc and phos protection. I went back and read your earlier thread and it is hard to argue about 0 wear, but our morning temps are lower than in OZ and our peak temps are rarely as high.
Maybe 2 bar is too low for a 928 at idle but that seems odd to me. It would never occur to me to be concerned about a car that idled at 28lbs of oil pressure at operating temp. I just put Mobil 1 10-30 in my car and I will be taking it out tomorrow; I will watch the pressures, but my car always idles at 3 bar and always hits 5 at redline. As a result of this thread I will probably go to 0-40 in the spring to get the additional phos and zink.
In defense of my logic (though I appreciate your insight on the bearing failure issues) if you look at Mobil 1's racing oil it is a very low viscocity high phos and zink formula. This provides minimum friction (more power) because of the low viscosity. , but top racing formulas use low viscosity oil for the reasons I described. For a competitive racing applications long engine life is not the primary issue and oil changes are often.
Last edited by turbochad; 10-04-2009 at 12:49 AM.
10-04-2009, 01:59 AM
#54
Drifting
Hi Turbochad , actually the owners manual says for a 20w-50 is an ambient temp range of minus 10 deg cel( 14 deg fah) to unlimited high temp , whats interesting is Porsche used to rate a 20w-50 down to minus 15 deg cel( 5 deg fah) ( I think pre 1980 ) in their owners manuals .
The reason I was pointing out the oil pressure gauge only going to 5 bar and not 10 bar that it should be like the 924 was is the words used most often in this subject is " The gauge is pegged at 5 bar " ,which is often terminology indicating that you have max oil pressure , but you have to ask yourself is it just on 5 bar or around 7 bar or even just under 8 bar ? , meaning you just do not know because the gauge supplied will not tell you .
I find it very interesting indeed that on the Mobil 1 racing web page it mentions that the ZDDP chemistries are twice that of their automotive street oils . The reason is that for this century Gas Powered (USA speak)/ Petrol powered cars have to comply to the ever stricter emmission proticols , ECEA etc , meaning the levels of ZDDP have to be reduced to comply and in their place is the later AW(anti wear) packages (read Boron etc) .
Now what I find amusing is that ZDDP is used at all in the Mobil 1 Racing oils and not just higher levels of the newer AW (anti wear) packages , so my question is why dont they just say that Mobil 1 Racing has twice the chemistries of the newer AW packages and no ZDDP at all .
Regards
BB
The reason I was pointing out the oil pressure gauge only going to 5 bar and not 10 bar that it should be like the 924 was is the words used most often in this subject is " The gauge is pegged at 5 bar " ,which is often terminology indicating that you have max oil pressure , but you have to ask yourself is it just on 5 bar or around 7 bar or even just under 8 bar ? , meaning you just do not know because the gauge supplied will not tell you .
I find it very interesting indeed that on the Mobil 1 racing web page it mentions that the ZDDP chemistries are twice that of their automotive street oils . The reason is that for this century Gas Powered (USA speak)/ Petrol powered cars have to comply to the ever stricter emmission proticols , ECEA etc , meaning the levels of ZDDP have to be reduced to comply and in their place is the later AW(anti wear) packages (read Boron etc) .
Now what I find amusing is that ZDDP is used at all in the Mobil 1 Racing oils and not just higher levels of the newer AW (anti wear) packages , so my question is why dont they just say that Mobil 1 Racing has twice the chemistries of the newer AW packages and no ZDDP at all .
Regards
BB
10-04-2009, 03:00 AM
#55
Rennlist Member
10-04-2009, 01:57 PM
#59
Nordschleife Master
Very interesting information. Some things to consider:
- Is there are difference between these oils in how easily they mix with air? Maybe some oils get whipped into a chocolate milk shake easier than others. Has anyone done a blender test with hot oils? Heat oil to a specific temperature, then poor it in a blender and see what comes out after say 20 second. If one were to run such a test, which five oils should one test?
- ZDDP kills cats. Without cats on, I don't think it has much direct emissions contribution. But car companies have to warranty the emissions equipment for approximately forever, so they will not want you running a high ZDDP concentration. Too low ZDDP level I believe shows up at the cams first. If the cams look good then there's no ZDDP problem. All these things considered, I was planning to run my car without cats and with a LOT of additives such as ZDDP while breaking in the cams.
- How does the bearing clearances figure out in all this? If people rebuild their engines with different bearings, say with the current Glycos that by reputation are tight, does that mean that they should also use lighter oils?
Just wondering.
- Is there are difference between these oils in how easily they mix with air? Maybe some oils get whipped into a chocolate milk shake easier than others. Has anyone done a blender test with hot oils? Heat oil to a specific temperature, then poor it in a blender and see what comes out after say 20 second. If one were to run such a test, which five oils should one test?
- ZDDP kills cats. Without cats on, I don't think it has much direct emissions contribution. But car companies have to warranty the emissions equipment for approximately forever, so they will not want you running a high ZDDP concentration. Too low ZDDP level I believe shows up at the cams first. If the cams look good then there's no ZDDP problem. All these things considered, I was planning to run my car without cats and with a LOT of additives such as ZDDP while breaking in the cams.
- How does the bearing clearances figure out in all this? If people rebuild their engines with different bearings, say with the current Glycos that by reputation are tight, does that mean that they should also use lighter oils?
Just wondering.
10-04-2009, 02:08 PM
#60
Racer
I run my 86.5 on 10w40 which is ok per the manual.
It gets hot here in Louisiana and even on 100 degree days with the ac running I get 3 bar at idle and anything over 3000rpm pegs the needle at 5 bar. My temp gauge under these conditions is always just below the mid point of the white lines.
I interpret this to mean my car is very happy and everything is in great shape. Thought about moving to 20w50 but see no real need given the above data?
Open to comments/suggestions......
It gets hot here in Louisiana and even on 100 degree days with the ac running I get 3 bar at idle and anything over 3000rpm pegs the needle at 5 bar. My temp gauge under these conditions is always just below the mid point of the white lines.
I interpret this to mean my car is very happy and everything is in great shape. Thought about moving to 20w50 but see no real need given the above data?
Open to comments/suggestions......