| Author |
Message |
Ali Haas (Aehaas)
New member
Username: Aehaas
Post Number: 11
Registered: 5-2003
| | Posted on Tuesday, May 20, 2003 - 2:11 pm: | |
Martin,
Use the oil that gives the appropriate pressure. My 575 M gets 80 PSI at 2,000 RPM at operating temperature around town in Sarasota. This is with the oil supplied with the car, having only 500 miles on it now. I think it is the Helix 5W-40.
Next I will try the 0W-30 and see what I get for pressures. As I stated earlier the manual says that the pressure should be 74 PSI at 6,000 RPM. In my 550 Maranello I got about 60 PSI at 2,000 - 2,500 RPM with 0W-30 Mobil 1. I was going to try the 5W-20 next but ended up trading it in on the 575.
aehaas |
Martin - Cavallino Motors (Miami348ts)
Advanced Member
Username: Miami348ts
Post Number: 4696
Registered: 5-2001
| | Posted on Tuesday, May 20, 2003 - 10:04 am: | |
Thanks,
now that you have totally confused me....
What should I drive as daily driver in Miami heat in my cars? Mostly engine temp does not come all the way up.
|
Ali Haas (Aehaas)
New member
Username: Aehaas
Post Number: 10
Registered: 5-2003
| | Posted on Monday, May 19, 2003 - 3:05 pm: | |
You oil people should also check out the forum called Gearbox Oil over in the Technical Q and A section.
aehaas |
Ken (Allyn)
Member
Username: Allyn
Post Number: 885
Registered: 10-2001
| | Posted on Thursday, May 15, 2003 - 12:02 pm: | |
Ben, thanks for the tip. I think I'll stick to the 20W50 after all. I change my oil all the time anyway (every 3 months which is typically 1000 miles or less) so I'm not losing any sleep having used 10W40. |
David Stoeppelwerth (Racerdj)
Junior Member
Username: Racerdj
Post Number: 171
Registered: 1-2003
| | Posted on Thursday, May 15, 2003 - 11:37 am: | |
Has anybody else noticed how the Shell Ultra Helix 5w40 resembles water in viscosity? |
Ben Millermon (Brainsboy)
Member
Username: Brainsboy
Post Number: 307
Registered: 5-2001
| | Posted on Wednesday, May 14, 2003 - 4:30 pm: | |
Ken did you read what the artical I posted? Perhaps you should read what it says about 10w40. |
Ken (Allyn)
Member
Username: Allyn
Post Number: 881
Registered: 10-2001
| | Posted on Wednesday, May 14, 2003 - 11:12 am: | |
Aehaas,
Thanks for your thoughts. I do run about 55-60 psi at 4k RPM which is higher than it used to be. The engine is a 32 year old Lotus/Ford Twincam with 52,000 miles on it. I was using 10W40 but was told by other owners that 20W50 is better for this engine. I've never had engine oil leaks regardless. Since it tends to run hot (never boiles over though) and I'm seeing higher oil pressure, I am thinking 10W40 might be a better idea after all from what you said. |
Ali Haas (Aehaas)
New member
Username: Aehaas
Post Number: 4
Registered: 5-2003
| | Posted on Wednesday, May 14, 2003 - 10:33 am: | |
Mixing synthetic and mineral oils together:
Some synthetic manufactures state that mixing with mineral oils is OK but not recommended. Most state that their synthetic should not be mixed with the other guys synthetic. Let us consider the mixing of a synthetic and a mineral oil together at a 50-50 ratio. The additives of each type of oil are then diluted 50-50. These are what make the oil perform better. If the additive is particular for the particular type of base oil then there must be a degradation of performance of the oil. The main reason that oil change intervals can be longer is because their additives last longer. The oil base itself does not change much. When the additives are used up so are the properties that make that oil perform. This is brought out in Sunny?s contribution.
I also believe that one needs to completely change the oil during an oil change. When my old 550 Maranello came back from the previous owner?s 15,000 mile service the oil was still dirty. I then changed it myself, about 13 quarts. It was still dirty. Then I changed it better. I took apart all the hoses from the engine to the oil tank, also the oil radiator. It too was emptied. I needed to add 3 more quarts to get it full. The filter of course always gets changed. Those hoses have about a one inch inside diameter. Without doing this extra work only 80 percent of the oil will get changed.
Oil change intervals have increased. This is in part due to better additives. Since engines are tighter there is also less blow by contamination. Also, engines have larger oil capacities. If your car holds 8 qts. and you somehow change it to 16 qts. it will last twice as long.
The clearest oil I have ever seen is Shell Helix Ultra. Many think that the more transparent the better the oil. This has some truth in that poor refining, ash, deposits and impurities will darken oils. However the newer oils have additives that are themselves dark colored. The 5W-20 Pennzoil I am now using in all my vehicles is dark from the bottle. They actually state on the label that one should not be alarmed. It is the new and better additives that give the oil in the can a dark color. If the additives were removed I would guess the base oil is highly refined and clear.
To answer some Q??s:
Ton, choose the oil viscosity that gives you the proper oil temperature and pressure under the conditions that you are driving. 10W-60 may be OK for an older, worn engine racing at top speed in the heat but is unlikely appropriate for around the town driving with a newer tight engine in the spring time. If it gives the right pressure Mobil 1 oil, probably the 0W-30 will give you a large boost in performance. People do not realize the performance hit they are taking using honey for oil.
Here is another good one:
Take a jar of new oil that has been sitting on the shelf for a while and empty it. Look in the bottom of the container. You will see some ?sludge?. This stuff as actually some of the additives that give the oil it?s attributes. Always shake that oil can well before you pour it into your engine. You paid for those additives, make sure they get into your engine.
aehaas |
Ali Haas (Aehaas)
New member
Username: Aehaas
Post Number: 3
Registered: 5-2003
| | Posted on Wednesday, May 14, 2003 - 10:28 am: | |
Mixing synthetic and mineral oils together:
Some synthetic manufactures state that mixing with mineral oils is OK but not recommended. Most state that their synthetic should not be mixed with the other guys synthetic. Let us consider the mixing of a synthetic and a mineral oil together at a 50-50 ratio. The additives of each type of oil are then diluted 50-50. These are what make the oil perform better. If the additive is particular for the particular type of base oil then there must be a degradation of performance of the oil. The main reason that oil change intervals can be longer is because their additives last longer. The oil base itself does not change much. When the additives are used up so are the properties that make that oil perform. This is brought out in Sunny?s contribution.
I also believe that one needs to completely change the oil during an oil change. When my old 550 Maranello came back from the previous owner?s 15,000 mile service the oil was still dirty. I then changed it myself, about 13 quarts. It was still dirty. Then I changed it better. I took apart all the hoses from the engine to the oil tank, also the oil radiator. It too was emptied. I needed to add 3 more quarts to get it full. The filter of course always gets changed. Those hoses have about a one inch inside diameter. Without doing this extra work only 80 percent of the oil will get changed.
Oil change intervals have increased. This is in part due to better additives. Since engines are tighter there is also less blow by contamination. Also, engines have larger oil capacities. If your car holds 8 qts. and you somehow change it to 16 qts. it will last twice as long.
The clearest oil I have ever seen is Shell Helix Ultra. Many think that the more transparent the better the oil. This has some truth in that poor refining, ash, deposits and impurities will darken oils. However the newer oils have additives that are themselves dark colored. The 5W-20 Pennzoil I am now using in all my vehicles is dark from the bottle. They actually state on the label that one should not be alarmed. It is the new and better additives that give the oil in the can a dark color. If the additives were removed I would guess the base oil is highly refined and clear.
To answer some Q??s:
Ton, choose the oil viscosity that gives you the proper oil temperature and pressure under the conditions that you are driving. 10W-60 may be OK for an older, worn engine racing at top speed in the heat but is unlikely appropriate for around the town driving with a newer tight engine in the spring time. If it gives the right pressure Mobil 1 oil, probably the 0W-30 will give you a large boost in performance. People do not realize the performance hit they are taking using honey for oil.
Here is another good one:
Take a jar of new oil that has been sitting on the shelf for a while and empty it. Look in the bottom of the container. You will see some ?sludge?. This stuff as actually some of the additives that give the oil it?s attributes. Always shake that oil can well before you pour it into your engine. You paid for those additives, make sure they get into your engine.
aehaas |
JRV (Jrvall)
Intermediate Member
Username: Jrvall
Post Number: 1439
Registered: 11-2002
| | Posted on Monday, May 12, 2003 - 10:44 pm: | |
>>This is what counts. It is normal for a higher temperature around town with less air flow through the radiators. What is your oil pressure at 4,000 RPM? It should be around 45 - 50 PSI with the engine hot. More than this indicates too thick an oil in my book. The function of oil is not just to lubricate. A major function is to cool those very hot bearing surfaces. Thinner oil means more flow means better cooling. <<
1- Ferrari Engines have "adjustable" Oil Pressure Relief Valves....so psi can be raised or lowered despite the oil viscosity and often the actual pressure setting is not factory manuel perfect.
2- The Dash Mounted Oil Pressure Gauges should "never be used" to determine "real" pressure, unless they have been checked against 'real calibrated' gauges, until then, they are only there as a guide.
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Sunny Garofalo (Jaguarxj6)
Member
Username: Jaguarxj6
Post Number: 426
Registered: 2-2003
| | Posted on Monday, May 12, 2003 - 7:33 pm: | |
Check out http://oilstudy.spacebears.com
Sunny |
Ben Millermon (Brainsboy)
Member
Username: Brainsboy
Post Number: 306
Registered: 5-2001
| | Posted on Monday, May 12, 2003 - 6:21 pm: | |
Frank,
I agree the redline looks pretty good, I wonder what the ash% and zinc% contents are. Next time you do an oil change see if the bottle has a 800 number to call. They may be able to supply some figures. |
Mitch Alsup (Mitch_alsup)
Member
Username: Mitch_alsup
Post Number: 647
Registered: 4-2002
| | Posted on Monday, May 12, 2003 - 5:33 pm: | |
"Ford now supplies most cars with 5 - 20 oil"
Engines built with more narrow clearences can tollerate oil with less viscosity. Engines built with carefully selected oil/scraper ring tension can tollerate lighter weight oils. Try 5-20 oil in a 65 Mustang and you will not like the repair bill.
"Thirty years ago automotive manufactures were recommending thicker oils for their engines. Now they are using thinner oils despite the fact that engines are designed to run hotter and tolerances are closer."
And the governmental pressure on fuel economy has nothing to do with it. Nor does the life of the engine (as long as its greater than the warentee period.) |
Ton Visser (Lion315)
Member
Username: Lion315
Post Number: 559
Registered: 12-2002
| | Posted on Monday, May 12, 2003 - 4:01 pm: | |
During my last oilservice the mechanic changed the oil of my 328 to Agip 10w60. What is your opinion on this?
Ton |
Ali Haas (Aehaas)
New member
Username: Aehaas
Post Number: 2
Registered: 5-2003
| | Posted on Monday, May 12, 2003 - 3:24 pm: | |
Second Wind:
What does that ASTM rating mean? Previous to the current standard of SL there was SJ, SH, SF, SE and so forth. SL became the revised standard in 2001 but oils with this label I have not seen on the market shelf until late last year. See ASTM standard D 4485-01a.
A sample of things measured in the test engine includes:
Viscosity increase rate, weighted piston deposit, average and maximum cam plus lifter wear, hot and cold stuck rings, low temperature viscosity performance, cam wear average and maximum, sludge rating, engine varnish rating, piston skirt varnish rating, oil screen clotting, oil screen debris, oil ring clogging, ball rust rating, several volatility loss tests, several foaming tests, several flow reduction tests with increasing water in oil content, homogeneity and miscibility tests.... to name a few.
If you want detailed information, just dream. You cannot just go to the ASTM web site and get specifics on the meaning or specifics of doing each test. They charge fees for this information.
All these tests must be met for the oil to get the SL rating. This is regardless of the viscosity in the range 0W-20 to 10W-30 for example. This again leads me to believe that the thinner oils are in fact better for your engine than the thicker ones as long as the average of 10 PSI per 1,000 RPM is met. This I take as an average rating. Less pressure or more pressure will increase wear and decrease performance.
To answer some Q?s:
Ken, watch your oil temperature. This is what counts. It is normal for a higher temperature around town with less air flow through the radiators. What is your oil pressure at 4,000 RPM? It should be around 45 - 50 PSI with the engine hot. More than this indicates too thick an oil in my book. The function of oil is not just to lubricate. A major function is to cool those very hot bearing surfaces. Thinner oil means more flow means better cooling.
In the late 1970?s after the gasoline crunch many cars were powered with turbo engines. Around that time Castrol came out with the 20W-50 GTX oil and everybody with a turbo used it. They got from 20,000 to 60,000 miles out of their turbos. My turbo cars got at least 100,000 and more. I just sold them after that so I do not know there actual lifespan. There was no oil consumption even at over 100,000 miles. I might add that I am always hot on the accelerator pedal when I drive. I like to spin my wheels at every opportunity. Back then all my cars ran Penzoil 5W-30 year round.
I agree with Hubert that one should stick with petroleum based oils for older cars with higher mileage because of leaking problems. However, if you live in harsh, cold climates during winter think again. Synthetic oils are much thinner and have much better flow rates at below 30 degree environments. Maybe they should be used for winter time only, even if there is some residual leaking when you go back to the mineral stuff for the summer.
Ross: You got it right! In the scheme of things oil is cheep.
My final observation:
Thirty years ago automotive manufactures were recommending thicker oils for their engines. Now they are using thinner oils despite the fact that engines are designed to run hotter and tolerances are closer. Mobil 1 0W20 is the latest addition to thin oils and 5-20 is becoming commonplace with every manufacturer. Previously I used Mobil 1 0W-30 in my V12 Mercedes and then switched to 5W-20 Pennzoil last year when it became available. This oil is thinner and I do not need the benefit of better flow in freezing temperature abilities of the synthetic here in Florida.
Again, the SAE numbers of 0W-20 and 5W-20 do not tell you much as the Mobil 1 and Pennzoil products I am comparing here have the same viscosities at the usual temperatures.
My Expedition went from 14.5 MPG around town to 15.5 MPG when I switched from 0W-30 Mobil 1 to Pennzoil 5W-20. I also changed to differential oil from Ford?s 75W-140 to Mobil 1 75W-90 gear oil. I never tow anything so I do not need a higher shear differential oil either.
aehaas |
Frank Parker (Parkerfe)
Intermediate Member
Username: Parkerfe
Post Number: 2288
Registered: 9-2001
| | Posted on Monday, May 12, 2003 - 3:23 pm: | |
Ben, I use Redline in my Boxer and from that chart it looks like it is about the best. |
Ben Millermon (Brainsboy)
Member
Username: Brainsboy
Post Number: 305
Registered: 5-2001
| | Posted on Monday, May 12, 2003 - 2:42 pm: | |
I had posted this site before about oil, its quite interesting.
http://www.vtr.org/maintain/oil-overview.html |
Hubert Otlik (Hugh)
Member
Username: Hugh
Post Number: 808
Registered: 1-2002
| | Posted on Monday, May 12, 2003 - 1:36 pm: | |
Mike: Synthetic oil is "thinner" v. conventional petroleum based dino juice oil. |
mike 308 (Concorde)
Junior Member
Username: Concorde
Post Number: 194
Registered: 8-2002
| | Posted on Monday, May 12, 2003 - 1:29 pm: | |
Hugh: Why would there be a potential problem if you "decide to go back" to synthetic after a switch? |
Ken (Allyn)
Member
Username: Allyn
Post Number: 875
Registered: 10-2001
| | Posted on Monday, May 12, 2003 - 12:53 pm: | |
Dave, yes; it's hotter due to less air flow. Regardless of the reason, wouldn't the engine oil also be hotter? I run 4-5k rpms around town usually which is where the engine seems happy (6800 redline). |
Dave (Maranelloman)
Intermediate Member
Username: Maranelloman
Post Number: 1503
Registered: 1-2002
| | Posted on Monday, May 12, 2003 - 12:45 pm: | |
Ken, perhaps less cooling air on the radiators around town? This would obviate any lower RPM's you are running in town quickly, I believe... |
Hubert Otlik (Hugh)
Member
Username: Hugh
Post Number: 806
Registered: 1-2002
| | Posted on Monday, May 12, 2003 - 12:32 pm: | |
Aeehas- This is to addrees your comments regarding the "thinner" nature of Mobil 1 (fully sythetic) v. petroleum based oils. Enjoy.
Synthetic vs. Conventional Oils:
The most striking difference b/w synthetic oils and conventional or so called petroleum based oils is the homogeneity of the carbon molecule(s) or -using the jargon- alkane(s) lengths. Meaning the composition and effectivly the weight of the synthetic oil is an exact defenition of the molecular composition of that oil. So, when you buy 10W-30 oil, its been engineered to have a composition of alkane's that give the oil an exact cold viscocity of 10W oil, and an operating temp viscocity of 30W oil. In contrast to petroleum/conventional or "dino juice" based oil, the alkane lengths are variable and have a compostion more akin to a polydispersed [short chains mixed along w/ medium length chains and long chain alkanes], than the monodispersed synthetic oil.
So, the weight of the conventinal oil is more of an estimate than an exact measurement, this is what makes the conventional oil more succeptible to breakdown. Much akin to knock in a combustion cycle, when and organic molecule under extreme heat and pressure can form a radical [ an atom with one lone electron] species-very reactive and dangerous- this causes a chain reaction w/in the combustion chamber, breaking down the surrounding carbon molecules and propogarting the formation of more and more radicals eventually leading to spontaneous combustion or knock. This spontanous radical formation is also possible w/ engine oil, when exposed to high heat the possibility of radical formation increases, the radical species formed is capable of reacting w/ the metals and material w/in the motor, and the surrounding oil particles-accelarating their degridation and breakdown-leading to a chain reaction that leads to the breakdown of the oil. Which can, at the extreme, cause metal to metal contact, gasket degridation-as we know rubber and plastic harden and become brittle when exposed to high temp/burned then allowed to cool.
Synthetic oil, however, is less likely to succumb to such conditions largly b/c of its greater degree of molecular homogeneity, hence it is able to provide a more consistant barrier b/w the surfaces w/ in the metal against thermal abrasion. And, it itself is more stable hence protecting the internal surfaces-sorry for the redundancy-against radical(s) and the damage therin. One tangential point, synthetic oils b/c of their molecular composition, are somewhat "thinner" than their conventional counterparts, again b/c the alkanes w/ in the oil are engineered to given lengths, unlike the petroleum based oils which are blended together during/after the cracking of the natural stock takes place. That is why some people have complained of leaks when switching to synthtic on a motor w/ high mileage and a lifetime of petroleum based oil use. Rule of thumb, if you've been using petroleum based oil for the majority of the engines life, keep using petroleum based oils, just change the oil more often. Conversly, there should be no ill side effects in going the opposite direction, meaning synthetic to pertroleum based, so go ahead. Keep in mind, however, that going back to synthetic may cause a problem, if you decide to go back.
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ross koller (Ross)
Intermediate Member
Username: Ross
Post Number: 1196
Registered: 3-2002
| | Posted on Monday, May 12, 2003 - 12:24 pm: | |
wow ! that is the most comprehensive dissertation i've read on motor oils. thx very much for sharing this info. i will definetely apply this knowledge.
in my case, i think an idea might be to just change the oil every time you do a track day. so keep the thin oil for around town, then change to thicker for the day out, then change the oil the next day for thinner around town again. guess the engine will also appreciate this frequent change as well. now all i need to do is figure out how i am going to do these changes myself.... |
Ken (Allyn)
Member
Username: Allyn
Post Number: 873
Registered: 10-2001
| | Posted on Monday, May 12, 2003 - 12:10 pm: | |
Very nice analysis. I'm confused on one point however. My car runs a lot hotter around town than on the highway (water temp that is). I can see a redline run for an hour being hot on the oil, but most of us run maybe 66% of redline in top gear. Would that still make highway driving hotter for the oil than around town? |
Ali Haas (Aehaas)
New member
Username: Aehaas
Post Number: 1
Registered: 5-2003
| | Posted on Monday, May 12, 2003 - 11:57 am: | |
Brian Willis has a lot of good info on an earlier post. However there are some oil misconceptions outstanding. The biggest one is that thicker oil is better. False. Higher speed turbines use thinner oil. Lubrication is not what you feel rubbing that oil between your fingers. Lubrication in engines is oil FLOW between moving parts.
The general saying that 90 percent of engine wear and tear occurs in cold engines is close to the truth. The most basic viscosity needs are defined by a pressure of 10 PSI per 1,000 RPM at operating temperature. My 575 M manual states the target pressure is 74 PSI at 6,000 RPM. The oil supplied with the car gives me about 80 PSI at 2,000 RPM, way too high. This is with around the town driving. I am sure that on the racetrack at full power and a hotter engine this thicker oil is fine. For my usual driving however, the thicker oil is causing more engine wear.
The manual of my old 550 Maranello gave only Shell Helix Ultra 5-40 for all uses. Oils are not that versatile. For around town use a thin oil, for the track use a thicker one. The new 575 manual states that the oil should be 15-50 for racing and 0-40 for around town. They are finally making more sense.
Oils are getting thinner. Ford now supplies most cars with 5 - 20 oil, previously it was 5 - 30. If you test different oils in your engine you will notice the engine oil temperature decreasing with thinner oils. At some point the next thinner oil will result in the engine temperature starting to go back up. This lowest temperature point is that with the least friction.
A friend recently changed from Mobil 1 15-50 in his big SUV to Penzoil 5-20 and went from 10 to 13 MPG around town. There was a slight decrease in engine oil temperature. The savings was also in cost for oil. His biggest enjoyment was the increase in get up and go power. For time trials all Indy and Stock cars use thinner oils to get more power. These oils will not stay thick enough for a long hot race but around the town driving is nothing like racing.
The last misconception I will tell you about is that those oil viscosity numbers on that oil can are not what you think at all. For example, Penzoil 100W EP gear oil is almost the exact same thickness as straight 30W engine oil. The additives are different. 10-30 Mobil 1 is thicker with a cold engine than 0-30 Mobil 1 but the 0-30 is actually thicker than the 10-30 with a hot engine. If you need a thicker oil with your hot engine the 0-30 is better than the 10-30 Mobil 1.
I am using 5-20 Penzoil in my V12 Mercedes sedan and V12 SL coupe. I use it in my Expedition as well. When I get to 1,000 miles on the 575 M I will change the oil to a thinner one and work my way down. I used 5-20 in my 550 Maranello around town. By the oil pressures I could have gone thinner yet. The recommended 5-40 for that car was only good for high speed racing in summer heat at Orlando Florida. Otherwise it was way too thick, increased engine wear, decreased power and gas mileage.
All Mobil 1 oil viscosities are lower than other brands with the same rating such as 10W-30. The oil is thinner and I think this contributes to the engine longevity they are claiming. Also, a thinner oil will make starting easier, the starter motor works less, lasts longer. Same for the battery. The lower temp under the hood increases the life of rubber and plastic parts. The list goes on.
Mr Willis said that the shear ratings were higher for synthetic lubes. I cannot find any data to support this. The high temperature shear ratings for Penzoil mineral oi 5W30 is 3.1 and the Synthetic Penzoil 5W-30 is 3.05. For Castol the numbers are 3.1 for the GTX mineral and 2.92 for the full Syntec. These numbers indicate that mineral based oils have better shear protection than the synthetic.
The above is my opinion based on years of research and data collection, speaking with people at SAE and individual oil companies chemists to mention a few.
aehaas |
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