OIL which brands burn good and which don't?
09-03-04, 02:58 AM
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Originally Posted by Rx7carl
Pele, read this.
Synthetic Oils
Snake or Miracle Oil?
You might be surprised to hear us referring to “synthetic oil” as “snake oil.” We have used synthetics since day one and switched completely to synthetics in 1993 when BMW endorsed their use. Thirteen years and tens of thousands of quarts of synthetic oil later, why then the sudden change? Because the name “synthetic oil” itself is not a true indicator of a premium quality product. Let’s dig a little deeper to understand why.
Group III and IV Base Stocks
The current definition of “synthetic oil” for labeling purposes includes Group III and Group IV base stocks. In simple terms, Group III is Group II conventional crude oil that undergoes additional processing. Group IV on the other hand is engineered oil built at the molecular level to produce a completely uniform base stock. We simply don’t believe crude oil refined extra steps qualifies as synthetic or that it will provide anywhere near the same level of protection.
Maybe you’re just jumping to conclusions here. Surely a respected scientific community made the determination that Group III oils were just as good as Group IV to be called synthetics! No. Ok, then it must have been an engineering community that could have proven the virtues of one against the other through comprehensive testing. Wrong again! The fact is that there is no definition offered by any respected scientific or engineering community defining what constitutes “synthetic oil.”
Ok, then who could have made such an important decision? Would you believe the National Advertising Division (NAD) of the Council of Better Business Bureaus? Why on earth would the NAD get involved in deciding what constitutes synthetic oil? It’s simple; in 1997 Castrol changed the base stock in their Syntec product line from Group IV to Group III. Complaints were filed against Castrol for continuing to call their product synthetic oil. Without any scientific or engineering definitions, the NAD took it upon themselves to make the determination. Since Group III is Group II processes through extra steps, the NAD felt it was a reasonable basis for the claim that Castrol Syntec was synthesized.
Since this momentous decision, a number of other companies have followed suit switching their synthetic products to Group III base stock. Most these products are still sold at a premium price level since consumers are willing to pay more for synthetics. The problem is that consumers are paying more because they believe they are getting a substantially better product! I believe people are buying “snake oil” they think is better due to a ruling by the NAD.
Group III vs. Group IV
Wait a minute, in testing Group III oils test almost as good as Group IV. Wouldn’t this be an indicator that Group III oils are just as good?
If you bought a new car you more than likely noticed the estimated fuel averages for city and highway driving. Like most of us, you probably haven’t seen that mileage other then on the sticker. Several factors affect your actual mileage including individual driving styles, engine break-in, gas quality, weather, road surface, etc. We all know these facts and realize these estimates are simply standardized measurements that allow us to compare different vehicles tested under the same conditions. It doesn’t mean we should expect that level of performance.
In a similar manner, oils are tested using an assortment of standardized tests. Oils can be compared against each other based on test results, chemical makeup and additives. In the real world, these oils are used in a wide variety of operating conditions and exposed to a number of contaminates including condensation, exhaust blow by and air particulate. Not to mention environmental conditions, vehicle maintenance and individual driver demand. All of these variables combined place unique demands on your oils. Here too, real world performance varies from the test environment.
We have first hand experience with the results of 3,000-6,000 miles of use on oils in the real world heat and humidity of Florida on a modern clean burning engine. Conventional oils are pushed to and in some cases beyond their limits. We were not surprised to see these oils breakdown under these conditions. What did surprise us was the poor performance of some synthetic oils.
Our records show which specific oil or oils were used in each and every service. We also ask new customers or those that do their own service what oils they use and when they last changed it when we find sludge for example in their motor.
Could the oil be breaking down because they are running it well beyond the recommended limits?
Is it a case that they are simply using low grade oils?
Almost everyone was following BMW's mileage and/or time recommendations for their oil changes. All the oils that performed poorly were either Group II or the "so called" synthetic Group III base stock oils!
Group IV Advantage
Crude oil is comprised of a wide range of different size molecules. The size of individual molecules ultimately determines the thickness or viscosity of the oil. The larger the molecule size, the thicker the oil. For engine oils, a medium sized molecule yields the desired fluid viscosity. Crude oil is refined to remove unwanted molecules. However, the resulting Group II and III products are still comprised of a cocktail of various size molecules.
In hot engines the smaller molecules evaporate which is generally perceived as oil consumption. Of greater concern is the fact that the remaining oil is thickening as a direct result of losing the smaller molecules. Larger molecules tend to have weaker bonds that break or sheer. Gears in motorcycle engines not typically found in automotive applications contribute to molecular sheer. The broken molecules bond with free oxygen or other free molecules growing into very large molecules forming sludge that further increases oil viscosity.
Group IV base stock oils are comprised of molecules that are all exactly the same size. These molecules are engineered to provide the desired viscosity and a very strong molecular bond. As a result, there are no small molecules to evaporate and molecules are highly resistant to breaking or shearing. Therefore, these oils are highly resistant to forming sludge or viscosity changes. Group IV oils hold up better in higher temperatures under all conditions.
Bottom Line
Now to answer the question regarding which oil type and approach is better.
Conventional oil (Group II or III) changed more frequently than the recommended interval.
Synthetics oil (Group IV) changed at the vehicle manufacturers recommended interval.
The fact is that a Group IV synthetic is the only way to go. Conventional oils do not hold up well in our experience even when changed at three times the recommended interval. If you calculate the just cost of the oil, filters and gaskets alone, it costs more. Then there's the issue of disposing of the waste oil and filter. These items are controlled substances in the State of Florida regulated by the Environmental Protection Agency (EPA).
Our first hand experience has shown that engineered Group IV synthetic base stock oils are still going strong at 6,000 miles. What happens if you're on the road traveling or something comes up and you accidentally run past the recommended change interval? Which oil would you rather have in the crankcase? Why put yourself through the extra work and expense of conventional oils. Do the job right and ride with confidence between services.
Just be on the look out for "snake oil" disguised as synthetic. You want to be sure you’re getting Group IV PAO base stock oils for your motor and driveline.
ã 2003 BMW of Orlando, Inc. All rights reserved
Synthetic Oils
Snake or Miracle Oil?
You might be surprised to hear us referring to “synthetic oil” as “snake oil.” We have used synthetics since day one and switched completely to synthetics in 1993 when BMW endorsed their use. Thirteen years and tens of thousands of quarts of synthetic oil later, why then the sudden change? Because the name “synthetic oil” itself is not a true indicator of a premium quality product. Let’s dig a little deeper to understand why.
Group III and IV Base Stocks
The current definition of “synthetic oil” for labeling purposes includes Group III and Group IV base stocks. In simple terms, Group III is Group II conventional crude oil that undergoes additional processing. Group IV on the other hand is engineered oil built at the molecular level to produce a completely uniform base stock. We simply don’t believe crude oil refined extra steps qualifies as synthetic or that it will provide anywhere near the same level of protection.
Maybe you’re just jumping to conclusions here. Surely a respected scientific community made the determination that Group III oils were just as good as Group IV to be called synthetics! No. Ok, then it must have been an engineering community that could have proven the virtues of one against the other through comprehensive testing. Wrong again! The fact is that there is no definition offered by any respected scientific or engineering community defining what constitutes “synthetic oil.”
Ok, then who could have made such an important decision? Would you believe the National Advertising Division (NAD) of the Council of Better Business Bureaus? Why on earth would the NAD get involved in deciding what constitutes synthetic oil? It’s simple; in 1997 Castrol changed the base stock in their Syntec product line from Group IV to Group III. Complaints were filed against Castrol for continuing to call their product synthetic oil. Without any scientific or engineering definitions, the NAD took it upon themselves to make the determination. Since Group III is Group II processes through extra steps, the NAD felt it was a reasonable basis for the claim that Castrol Syntec was synthesized.
Since this momentous decision, a number of other companies have followed suit switching their synthetic products to Group III base stock. Most these products are still sold at a premium price level since consumers are willing to pay more for synthetics. The problem is that consumers are paying more because they believe they are getting a substantially better product! I believe people are buying “snake oil” they think is better due to a ruling by the NAD.
Group III vs. Group IV
Wait a minute, in testing Group III oils test almost as good as Group IV. Wouldn’t this be an indicator that Group III oils are just as good?
If you bought a new car you more than likely noticed the estimated fuel averages for city and highway driving. Like most of us, you probably haven’t seen that mileage other then on the sticker. Several factors affect your actual mileage including individual driving styles, engine break-in, gas quality, weather, road surface, etc. We all know these facts and realize these estimates are simply standardized measurements that allow us to compare different vehicles tested under the same conditions. It doesn’t mean we should expect that level of performance.
In a similar manner, oils are tested using an assortment of standardized tests. Oils can be compared against each other based on test results, chemical makeup and additives. In the real world, these oils are used in a wide variety of operating conditions and exposed to a number of contaminates including condensation, exhaust blow by and air particulate. Not to mention environmental conditions, vehicle maintenance and individual driver demand. All of these variables combined place unique demands on your oils. Here too, real world performance varies from the test environment.
We have first hand experience with the results of 3,000-6,000 miles of use on oils in the real world heat and humidity of Florida on a modern clean burning engine. Conventional oils are pushed to and in some cases beyond their limits. We were not surprised to see these oils breakdown under these conditions. What did surprise us was the poor performance of some synthetic oils.
Our records show which specific oil or oils were used in each and every service. We also ask new customers or those that do their own service what oils they use and when they last changed it when we find sludge for example in their motor.
Could the oil be breaking down because they are running it well beyond the recommended limits?
Is it a case that they are simply using low grade oils?
Almost everyone was following BMW's mileage and/or time recommendations for their oil changes. All the oils that performed poorly were either Group II or the "so called" synthetic Group III base stock oils!
Group IV Advantage
Crude oil is comprised of a wide range of different size molecules. The size of individual molecules ultimately determines the thickness or viscosity of the oil. The larger the molecule size, the thicker the oil. For engine oils, a medium sized molecule yields the desired fluid viscosity. Crude oil is refined to remove unwanted molecules. However, the resulting Group II and III products are still comprised of a cocktail of various size molecules.
In hot engines the smaller molecules evaporate which is generally perceived as oil consumption. Of greater concern is the fact that the remaining oil is thickening as a direct result of losing the smaller molecules. Larger molecules tend to have weaker bonds that break or sheer. Gears in motorcycle engines not typically found in automotive applications contribute to molecular sheer. The broken molecules bond with free oxygen or other free molecules growing into very large molecules forming sludge that further increases oil viscosity.
Group IV base stock oils are comprised of molecules that are all exactly the same size. These molecules are engineered to provide the desired viscosity and a very strong molecular bond. As a result, there are no small molecules to evaporate and molecules are highly resistant to breaking or shearing. Therefore, these oils are highly resistant to forming sludge or viscosity changes. Group IV oils hold up better in higher temperatures under all conditions.
Bottom Line
Now to answer the question regarding which oil type and approach is better.
Conventional oil (Group II or III) changed more frequently than the recommended interval.
Synthetics oil (Group IV) changed at the vehicle manufacturers recommended interval.
The fact is that a Group IV synthetic is the only way to go. Conventional oils do not hold up well in our experience even when changed at three times the recommended interval. If you calculate the just cost of the oil, filters and gaskets alone, it costs more. Then there's the issue of disposing of the waste oil and filter. These items are controlled substances in the State of Florida regulated by the Environmental Protection Agency (EPA).
Our first hand experience has shown that engineered Group IV synthetic base stock oils are still going strong at 6,000 miles. What happens if you're on the road traveling or something comes up and you accidentally run past the recommended change interval? Which oil would you rather have in the crankcase? Why put yourself through the extra work and expense of conventional oils. Do the job right and ride with confidence between services.
Just be on the look out for "snake oil" disguised as synthetic. You want to be sure you’re getting Group IV PAO base stock oils for your motor and driveline.
ã 2003 BMW of Orlando, Inc. All rights reserved
http://www.xs11.com/stories/croil96.htm
This independent test cofirmed dino and synthetic motor oils do not show any measureable difference in engine wear over 60K miles of testing.
Personally, I have always used store brand 10w30 stock Dino oil from auto parts retailers at approx. $1.00 per qt. in my 1988 RX7 SE non-turbo with 230K original miles (car bought new in 1988). According to Mazda dealer, original rotary engine pulls strong and compression is satisfactory at 7.5 for rear and 8.1 for front chamber. Car idles at 750 rpms with minimal engine vibration and it burns 1 qt. of oil every 700-800 miles.
Gordon
Last edited by gbowers; 09-03-04 at 03:08 AM.
03-21-05, 07:47 PM
#78
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Ok so whats the general consensus?
Looks like 50/50 to me, basically if you like syns use syns, if you like dyno use dyno.
Now for this question, if you have been using dyno for 70k miles is it bad to just switch to synthetics and if so why, and what should you do to correct the problem.
Looks like 50/50 to me, basically if you like syns use syns, if you like dyno use dyno.
Now for this question, if you have been using dyno for 70k miles is it bad to just switch to synthetics and if so why, and what should you do to correct the problem.
01-04-06, 11:32 AM
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No Omp, 15w50 Mobil One Synthetic (gold cap), Mobil One Oil Filter, Belray Synthetic 2 stroke oil premixed at 3 oz. per 5 gal. Have never had a problem in two years and 6 autox and 5 250+mile track weekends with lots of 7k+rpms.
Love synthetics, Love my car.
Love synthetics, Love my car.
01-04-06, 10:17 PM
#85
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So does anybody have any bad experiences with synthetic oils using the OMP? It seems like a no brainer, if a true synthetic oil is uniform, and dino oil has both smaller and larger molocules. Wouldn't the dino oil have more potential to create unwanted deposites because it can have both overly small and overly large molecules, the latter i would assume to be the cause of thick deposits.
05-05-06, 11:49 PM
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My dad and I used to desert race dirt bikes in eastern WA, and running a 125cc in the deep sand was really hard on the engine. Every couple of races I was replacing the piston, ring, and wrist pin. We experimented with several 2 stroke premixes and found that Golden Spectro synthetic premix yielded the best wear protection and clean burn. Si-7, Bel-ray, and Yamalube(they are all the same I think-blue colored) also worked well for wear but didn't burn quite as clean.
My main complaint about the rotary's oiling system is that motor oil is not designed to burn. It builds up nasty carbon deposits that don't do the engine any good. Pre-mix is designed to burn and leaves minimal carbon. I made a block off plate for the metering pump and I run 4oz Golden Spectro to 5 gallons Gas in my autocross car. On a street car you can probably go 5oz per tank maybe less and it will be fine. I noticed right away that high rpm revs were smoother and a little quicker, maybe a few more HP?
The golden spectro is availiable at most motorcycle shops in a 1/2 gallon size that last's along time. Last one I bought cost me $20 maybe a little more by now though. It usually lasts me a season of autocross. For autocross I run castrol GTX 20w-50 for motor oil, and in a my 1st gen roadrace car(sold to boswoj) synthetic only. Regular oil turns to water under sustained high rpm use.
Just my .02
My main complaint about the rotary's oiling system is that motor oil is not designed to burn. It builds up nasty carbon deposits that don't do the engine any good. Pre-mix is designed to burn and leaves minimal carbon. I made a block off plate for the metering pump and I run 4oz Golden Spectro to 5 gallons Gas in my autocross car. On a street car you can probably go 5oz per tank maybe less and it will be fine. I noticed right away that high rpm revs were smoother and a little quicker, maybe a few more HP?
The golden spectro is availiable at most motorcycle shops in a 1/2 gallon size that last's along time. Last one I bought cost me $20 maybe a little more by now though. It usually lasts me a season of autocross. For autocross I run castrol GTX 20w-50 for motor oil, and in a my 1st gen roadrace car(sold to boswoj) synthetic only. Regular oil turns to water under sustained high rpm use.
Just my .02
Last edited by rkcarguy; 05-05-06 at 11:57 PM.
05-06-06, 02:07 AM
#91
FB+FC=F-ME
Originally Posted by smnc
Idemitsu... Synthetic designed for a Rotary...
What more endorsement could you ask for, in regards to synthetics and rotaries?
Just run Idemitsu, and shut up!!
Or dont,and save some money.....your choice........and shut up!,heh,heh.
05-06-06, 02:24 PM
#92
There is nothing special about Idemitsu. I've seen an oil test on it that shows what it is made of. The only thing it has on an oil like Royal Purple is that it contains unusually high levels of molybdenum. That is a lubricant but it also has a tendency to settle out and gum up in low spots. I'm not going to use it in a street car but if you guys are naive enough to actually believe that it is somehow formulated for a rotary while others aren't, more power to you. Ignornace is bliss.
Did it ever occur to anyone that since Idemitsu is a sponsor of Mazda's racing program and that Mazda engineers helped in the development of it that of course they would say it is rotary formulated? There's nothing special about it. It's all the same chemicals as other good oils being applied to a group IV PAO base stock. It's the base stock that makes it a "synthetic". Did you guys ever stop to think that if an independent company had formulated the exact same oil without Mazda there that Mazda probably wouldn't endorse it? They wouldn't! Shell oil pays nearly a quarter of a billion a year to Ferrari. Where do you think their F1 team and Michael Schumacher get all of their money from? Shell Oil! Does this mean that Shell oil that is "specially formulated" for Ferrari is somehow special compared to others? I think not. Idemitsu is basically more expensive Royal Purple or any other good synthetic. There is no advantage to it. It's marketing and you guys believe it. It's not a bad oil by any means. It's good stuff. There is just nothing special about it.
Did it ever occur to anyone that since Idemitsu is a sponsor of Mazda's racing program and that Mazda engineers helped in the development of it that of course they would say it is rotary formulated? There's nothing special about it. It's all the same chemicals as other good oils being applied to a group IV PAO base stock. It's the base stock that makes it a "synthetic". Did you guys ever stop to think that if an independent company had formulated the exact same oil without Mazda there that Mazda probably wouldn't endorse it? They wouldn't! Shell oil pays nearly a quarter of a billion a year to Ferrari. Where do you think their F1 team and Michael Schumacher get all of their money from? Shell Oil! Does this mean that Shell oil that is "specially formulated" for Ferrari is somehow special compared to others? I think not. Idemitsu is basically more expensive Royal Purple or any other good synthetic. There is no advantage to it. It's marketing and you guys believe it. It's not a bad oil by any means. It's good stuff. There is just nothing special about it.
05-06-06, 10:13 PM
#93
FB+FC=F-ME
That may be, and I dont argue those points.
But for the skepictal,worrysome and/or downright confused....... if I/you/they had to choose between one syn. oil that says its fine to run in rotaries and another syn oil that Mazda had a part in making for rotaries,Ill take the one with Mazda involvement,regardless of whether they were the same chemically. After all,who knows better than Mazda whats good for their engines?
But for the skepictal,worrysome and/or downright confused....... if I/you/they had to choose between one syn. oil that says its fine to run in rotaries and another syn oil that Mazda had a part in making for rotaries,Ill take the one with Mazda involvement,regardless of whether they were the same chemically. After all,who knows better than Mazda whats good for their engines?
05-06-06, 10:19 PM
#94
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Originally Posted by steve84GS TII
After all,who knows better than Mazda whats good for their engines?
As far as I am concerned, so long as you maintain proper intervals of changing the oil, it doesn't really make a difference what oil you use. Oils nowadays are lightyears ahead of oils of old, so I would imagine they also burn much cleaner.
05-06-06, 11:10 PM
#95
FB+FC=F-ME
True,but apparantly Idemitsu rotary oil was developed a while back,during the Lemans days of the 787B,when rotaries were still a common sight and second gens were still considered new cars.Nowadays, I wouldnt expect many dealers to have rotary competent mechanics around, since rotaries/RX-7s havent sold in high numbers in the last 15-16 years......I wont even bring up the RX-8.
I also agree that oil changes are the most important issue,but the small cost of premium oil is a minor thing when weighed against an expensive engine/turbo combination thats expected to live a long life.I dont mind paying out for Royal Purple,or paying even a little more for Idemitsu.Its only a few dollors more,twice a year....not a big deal when compared to gas,tires,insurance and all the other stuff that needs attention too.
http://www.mazdatrix.com/faq/synthetc.htm
I also agree that oil changes are the most important issue,but the small cost of premium oil is a minor thing when weighed against an expensive engine/turbo combination thats expected to live a long life.I dont mind paying out for Royal Purple,or paying even a little more for Idemitsu.Its only a few dollors more,twice a year....not a big deal when compared to gas,tires,insurance and all the other stuff that needs attention too.
http://www.mazdatrix.com/faq/synthetc.htm
Last edited by steve84GS TII; 05-06-06 at 11:25 PM.
05-07-06, 09:00 AM
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I too use all Amsoil products in the 7. Tranny, diff and engine. I still change the oil at 3 -5k, depending on whether or not I have driven her hard for that period or not. As Aussie stated, quiter and more powerful as well as freer reving. Anyone that I have convinced to use Amsoil products will no longer go back to a conventional or other synthetic. The only question mark is how well does it burn in our rotarys. Until someone tears down a rotary that used strictly Amsoil we will never know the truth to any opinions on the "burning" properties.
05-07-06, 11:28 AM
#98
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I use 10w-30 Valvoline. Valvoline because one of the guys on the forum was an API member and said it has lower ash, which is probably good. 10w-30 because it's manufacturer recommended. I'm leary about using 40 and 50 weight oils because they may be inferior to right-weight oil under the moderate temperature loads of non-race cars. The knowledgeable Mechanical Engineer I used to prep race cars with said that the higher shear strength of heavy oil could cause tearing in tight clearances at high RPM, thus loss of lube effect. We only used it in race engines that had been prepared by opening up the clearances to accomodate the heavier oil.
05-07-06, 12:05 PM
#99
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Incidentally, there are good reasons for opening clearances, especially on a race engine (but you race guys probably know this, so pardon me): more oil passes thru bearings improving cooling and film strength, less sensitivity to suspended particles, and less sensitivity to varying tolerances in bearings. Of course that necessitates opening piston tolerances in a boinger (I expect there's a similar requirement to avoid apex seal breakage in the rotary) to reduce cylinder wall galling and piston ring breakage.
Heavier oil is not necessarily better oil, even in an old engine. Following the notion of heavier is better could ruin an engine in the mistaken idea that one is helping. I'm running an SE with 150k and a GS with 130k with 10w-30 and they are both smooth and make no noises on startup and don't burn excess oil.
Oil doesn't wear out. We change oil because it gets dirty and the beneficial additives burn off with mileage. Instead of throwing out good oil (that happens to be dirty and depleted viscosity-point suppressants that result in 10w-30 becoming plain old 30), one might be better advised to change oil filters more regularly. Much easier. Oil can be reclaimed by filtering thru diatomaceous earth, and that's what I used when I was a poor student, for 25 cents a quart.
Heavier oil is not necessarily better oil, even in an old engine. Following the notion of heavier is better could ruin an engine in the mistaken idea that one is helping. I'm running an SE with 150k and a GS with 130k with 10w-30 and they are both smooth and make no noises on startup and don't burn excess oil.
Oil doesn't wear out. We change oil because it gets dirty and the beneficial additives burn off with mileage. Instead of throwing out good oil (that happens to be dirty and depleted viscosity-point suppressants that result in 10w-30 becoming plain old 30), one might be better advised to change oil filters more regularly. Much easier. Oil can be reclaimed by filtering thru diatomaceous earth, and that's what I used when I was a poor student, for 25 cents a quart.
05-13-06, 11:17 PM
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I want to add that oil weight needs to be choosen by application. Hotter climates, daily driver or race car, lots of highway driving or 2 miles of stop and go to work each day? These all decide what oil weight should be used. Crap oil doesn't hold it's weight in my autocross car. 10w-30 and 10w-40 turns into water and I get a whole 15-18 PSI of oil pressure at idle when hot......not good. I run the 20w-50 and have no problems, but I never rip on it when cold. I always let the engine come up to temp and the oil pressure starts out high then warms up and drops to around 30psi at idle. In short, run whatever oil you want, but if you notice your idle oil pressure is low when hot you need either heavier oil or switch to synthetic.