Mobil 1 synthetic 15w-50 $4.74 qt
03-14-2007, 02:26 AM
#61
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Originally Posted by mark kibort
one thing i would critize, is the use of 40 weight, when porsche calls out for 20-50 for the normal temp ranges.
www.landsharkoz.com/tt/tt_pao.htm
03-14-2007, 02:31 AM
#62
Rennlist Member
Doug,
so,if you are using oils in extreme conditions, would it be better to use the single grade oils for the gain in stability? most real racing oil is single grade, but im hung up with the wear on start up thing with an oil that is to thick to start
speaking of filters, you should have seen the World Challenge Viper comp coupe that grenaded at the race a few years ago. the cheapo Mopar oil filter check valve (?) stuck and oil didnt flow. the car looked like a V2 rocket when it grenaded! all because of a cheap filter. what do you think it cost to rebuld that 10 cylinder !!!!!
Mk
so,if you are using oils in extreme conditions, would it be better to use the single grade oils for the gain in stability? most real racing oil is single grade, but im hung up with the wear on start up thing with an oil that is to thick to start
speaking of filters, you should have seen the World Challenge Viper comp coupe that grenaded at the race a few years ago. the cheapo Mopar oil filter check valve (?) stuck and oil didnt flow. the car looked like a V2 rocket when it grenaded! all because of a cheap filter. what do you think it cost to rebuld that 10 cylinder !!!!!
Mk
Originally Posted by Doug Hillary
Hi,
one of the problems with oil filters Mark is the very issue you raise - oil temperature!
I would ONLY use a OEM filter on a 928 and change it annually or at 20kkms whichever comes first. The OEM filter(s) are very well constructed with valving and filtering media that matches the high relief valve settings used on Porsche engines
Non OEM or substandard filters tend to self destruct if the seals, glues and media are not durable and usually their media and differential by-pass setting are unreliable. High oil temperatures tend to accellerate this process
As for SAE40 viscosity oils, well they are not all built the same and instead of focusing on the vaiscosity at 100C it is much better to have a relaible and sustainable High Temperature High Shear (HTHS) viscosity (measured at 150C) than a SAE50 oil with an unreliable one
The main OEM "user" viscosities are;
SAE20 (0w-20 and etc)
SAE30 (0w-30 and etc)
SAE40 (0w-40 and etc)
SAE50 (0w-50 and etc)
So an SAE40 luubricant is at the high end of things considering Porsche factory filled for years with Shell Rotella (Rimula) HDEO SAE30 monograde in all air coolled engines for many many years!
The main thing for street use is to use an Approved oil that has a 0w or 5W "cold" rating
Approved oils meet stringent tests determined by the Engineers who made the engines. The tests are very specific with regard to HTHS and 100C viscosity over extended periods along with foaming control and strict volatility parameters. There are other protocols too
The normal and most desirable oil temperature operating range in a 928 is from around 92C to 110C and up to 120C is no issue with Approved oils. It is better to operate with hot oil in this range than to try and run oil too cool
Regards
one of the problems with oil filters Mark is the very issue you raise - oil temperature!
I would ONLY use a OEM filter on a 928 and change it annually or at 20kkms whichever comes first. The OEM filter(s) are very well constructed with valving and filtering media that matches the high relief valve settings used on Porsche engines
Non OEM or substandard filters tend to self destruct if the seals, glues and media are not durable and usually their media and differential by-pass setting are unreliable. High oil temperatures tend to accellerate this process
As for SAE40 viscosity oils, well they are not all built the same and instead of focusing on the vaiscosity at 100C it is much better to have a relaible and sustainable High Temperature High Shear (HTHS) viscosity (measured at 150C) than a SAE50 oil with an unreliable one
The main OEM "user" viscosities are;
SAE20 (0w-20 and etc)
SAE30 (0w-30 and etc)
SAE40 (0w-40 and etc)
SAE50 (0w-50 and etc)
So an SAE40 luubricant is at the high end of things considering Porsche factory filled for years with Shell Rotella (Rimula) HDEO SAE30 monograde in all air coolled engines for many many years!
The main thing for street use is to use an Approved oil that has a 0w or 5W "cold" rating
Approved oils meet stringent tests determined by the Engineers who made the engines. The tests are very specific with regard to HTHS and 100C viscosity over extended periods along with foaming control and strict volatility parameters. There are other protocols too
The normal and most desirable oil temperature operating range in a 928 is from around 92C to 110C and up to 120C is no issue with Approved oils. It is better to operate with hot oil in this range than to try and run oil too cool
Regards
03-14-2007, 02:53 AM
#63
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Hi Mark,
Now that Viper's engine would have been something to see!
Mono (single) viscosity oils were once the darling of the racing set as you know. And yes, cold start up wear and poor component actuation is a real problem with many engine families
Todays multigrade synthetic oils are wonderful chemical cocktails and I think what you use has done you well in your application. And, as you say you warm the oil to around 80C before seriously loading the engine this is an excellent and very professional practice in the use of that product
In very "old" engines (and I must be careful to use the correct words) sometimes mineral or semi synthetic oils in the 20w-50 range do a marvellous job. Some (I will not use the Brand name) appear to be outstanding in these applications. But NOT for street use!!!!
Many older air cooled 911 racers here use 15w-40 HDEOs like Delo 400, Delvac 1300?, Shell Rotella etc and as these oils are very similar to the earlier factory fills they are ideal. Most have very good cold start performance, a great HTHS viscosity, resist corrosion very well. Some are now available as a semi synthetic in the USA, Shell's Rotella SB Synthetic Blend 10w-40 is just one.
I'm very biased of course as I have used these HDEOS since the late 1950s in VWs and Porsches and many problem engines with great results. And I used them in my trucks of course before going to a full synthetic
The likes of V300 Motul Competition 15w-50 and Castrol's 10w-60 mentioned earlier are excellent in overfuelled or carburettored engines used in (especially) long duration races
Regards
Now that Viper's engine would have been something to see!
Mono (single) viscosity oils were once the darling of the racing set as you know. And yes, cold start up wear and poor component actuation is a real problem with many engine families
Todays multigrade synthetic oils are wonderful chemical cocktails and I think what you use has done you well in your application. And, as you say you warm the oil to around 80C before seriously loading the engine this is an excellent and very professional practice in the use of that product
In very "old" engines (and I must be careful to use the correct words) sometimes mineral or semi synthetic oils in the 20w-50 range do a marvellous job. Some (I will not use the Brand name) appear to be outstanding in these applications. But NOT for street use!!!!
Many older air cooled 911 racers here use 15w-40 HDEOs like Delo 400, Delvac 1300?, Shell Rotella etc and as these oils are very similar to the earlier factory fills they are ideal. Most have very good cold start performance, a great HTHS viscosity, resist corrosion very well. Some are now available as a semi synthetic in the USA, Shell's Rotella SB Synthetic Blend 10w-40 is just one.
I'm very biased of course as I have used these HDEOS since the late 1950s in VWs and Porsches and many problem engines with great results. And I used them in my trucks of course before going to a full synthetic
The likes of V300 Motul Competition 15w-50 and Castrol's 10w-60 mentioned earlier are excellent in overfuelled or carburettored engines used in (especially) long duration races
Regards
03-14-2007, 03:50 AM
#64
Rennlist Member
Thanks Doug.
yes, that viper was a major event in itself. i think it was Mosport a couple of years ago.
By the way, great information along the way. I have little knowledge of the true science of the oils we discuss, only what ive read and what you have posted here (and the pressures ive seen at the track with different types of oils, and the fact that my car is still running!!)
Mark
yes, that viper was a major event in itself. i think it was Mosport a couple of years ago.
By the way, great information along the way. I have little knowledge of the true science of the oils we discuss, only what ive read and what you have posted here (and the pressures ive seen at the track with different types of oils, and the fact that my car is still running!!)
Mark
Originally Posted by Doug Hillary
Hi Mark,
Now that Viper's engine would have been something to see!
Mono (single) viscosity oils were once the darling of the racing set as you know. And yes, cold start up wear and poor component actuation is a real problem with many engine families
Todays multigrade synthetic oils are wonderful chemical cocktails and I think what you use has done you well in your application. And, as you say you warm the oil to around 80C before seriously loading the engine this is an excellent and very professional practice in the use of that product
In very "old" engines (and I must be careful to use the correct words) sometimes mineral or semi synthetic oils in the 20w-50 range do a marvellous job. Some (I will not use the Brand name) appear to be outstanding in these applications. But NOT for street use!!!!
Many older air cooled 911 racers here use 15w-40 HDEOs like Delo 400, Delvac 1300?, Shell Rotella etc and as these oils are very similar to the earlier factory fills they are ideal. Most have very good cold start performance, a great HTHS viscosity, resist corrosion very well. Some are now available as a semi synthetic in the USA, Shell's Rotella SB Synthetic Blend 10w-40 is just one.
I'm very biased of course as I have used these HDEOS since the late 1950s in VWs and Porsches and many problem engines with great results. And I used them in my trucks of course before going to a full synthetic
The likes of V300 Motul Competition 15w-50 and Castrol's 10w-60 mentioned earlier are excellent in overfuelled or carburettored engines used in (especially) long duration races
Regards
Now that Viper's engine would have been something to see!
Mono (single) viscosity oils were once the darling of the racing set as you know. And yes, cold start up wear and poor component actuation is a real problem with many engine families
Todays multigrade synthetic oils are wonderful chemical cocktails and I think what you use has done you well in your application. And, as you say you warm the oil to around 80C before seriously loading the engine this is an excellent and very professional practice in the use of that product
In very "old" engines (and I must be careful to use the correct words) sometimes mineral or semi synthetic oils in the 20w-50 range do a marvellous job. Some (I will not use the Brand name) appear to be outstanding in these applications. But NOT for street use!!!!
Many older air cooled 911 racers here use 15w-40 HDEOs like Delo 400, Delvac 1300?, Shell Rotella etc and as these oils are very similar to the earlier factory fills they are ideal. Most have very good cold start performance, a great HTHS viscosity, resist corrosion very well. Some are now available as a semi synthetic in the USA, Shell's Rotella SB Synthetic Blend 10w-40 is just one.
I'm very biased of course as I have used these HDEOS since the late 1950s in VWs and Porsches and many problem engines with great results. And I used them in my trucks of course before going to a full synthetic
The likes of V300 Motul Competition 15w-50 and Castrol's 10w-60 mentioned earlier are excellent in overfuelled or carburettored engines used in (especially) long duration races
Regards
03-14-2007, 06:56 AM
#65
Race Car
So what is a guy supposed to use for a dual purpose car: street/track?
I have been "happily" running street tires at the track to help avoid the legendary 1-6 failure. I have never seen oil pressure drop below 4.5. Operating temps have never gotten out of control.
Several years ago, I abandoned Mobil 1 after years and years of use. I don't want to do an oil change before every track event if I don't have to and don't want an oil that needs too much warm up time. Exiting our neighborhood and the office park I work in frequently requires a short blast of acceration (or more patience). Seems the best for track is the worst for daily driving?
I have been "happily" running street tires at the track to help avoid the legendary 1-6 failure. I have never seen oil pressure drop below 4.5. Operating temps have never gotten out of control.
Several years ago, I abandoned Mobil 1 after years and years of use. I don't want to do an oil change before every track event if I don't have to and don't want an oil that needs too much warm up time. Exiting our neighborhood and the office park I work in frequently requires a short blast of acceration (or more patience). Seems the best for track is the worst for daily driving?
03-14-2007, 07:12 AM
#66
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Hi Mark,
My engine failure at Sebring (1986.5 928S, stock engine with 125K+miles, recently replaced con-rod bearings 2-3K miles ago, GTS baffled, accusumped, Mobil 1 15-50 oil) I do not believe was showing any low pressure indications before the engine let go. The car was being driven by Mark Anderson who was probably driving it faster/harder than ever in it's life. The engine let go on the last lap after about 43 minutes of racing and just after completing a very fast, high G, left hand turn (turn 1) that is often sited to be the very worst for optimizing the engine design's weak points for getting oil to the 2/6 con rod bearings.
I still have not investigated the reason for the failure just yet so cannot comment/confirm it really was the 2/6 rod bearings. I did however notice the accusump acting a bit sluggish in discharging the oil when tripping the switch before engine start ups which might have been a contributing factor. I am planning on sending the accusump to Canton to have them go through it.
Great oil discussion by the way,
Constantine
Mark K. Qoute:
"Most recently, the failure at Sebring, coupled with the low pressure indications, makes me very nervous about the performance of Mobil 1, for our cars, in high temp activities.
Mk"
My engine failure at Sebring (1986.5 928S, stock engine with 125K+miles, recently replaced con-rod bearings 2-3K miles ago, GTS baffled, accusumped, Mobil 1 15-50 oil) I do not believe was showing any low pressure indications before the engine let go. The car was being driven by Mark Anderson who was probably driving it faster/harder than ever in it's life. The engine let go on the last lap after about 43 minutes of racing and just after completing a very fast, high G, left hand turn (turn 1) that is often sited to be the very worst for optimizing the engine design's weak points for getting oil to the 2/6 con rod bearings.
I still have not investigated the reason for the failure just yet so cannot comment/confirm it really was the 2/6 rod bearings. I did however notice the accusump acting a bit sluggish in discharging the oil when tripping the switch before engine start ups which might have been a contributing factor. I am planning on sending the accusump to Canton to have them go through it.
Great oil discussion by the way,
Constantine
Mark K. Qoute:
"Most recently, the failure at Sebring, coupled with the low pressure indications, makes me very nervous about the performance of Mobil 1, for our cars, in high temp activities.
Mk"
03-14-2007, 09:53 AM
#67
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And Mark, Castrol's "R" or Edge fully synthetic 10w-60 is probably one of the Worlds best racing oils in the correct application.
Available at your local BMW dealer.
03-14-2007, 11:29 AM
#68
Rennlist Member
Doug,
In light of the fact that anti-wear additives are decreasing in most oils how about motorcycle oils?
This link is a study paper: http://www.syntheticwarehouse.com/br..._oil_study.pdf
In light of the fact that anti-wear additives are decreasing in most oils how about motorcycle oils?
This link is a study paper: http://www.syntheticwarehouse.com/br..._oil_study.pdf
03-14-2007, 12:22 PM
#69
Burning Brakes
I've been able to find Shell Rotella T Multi Grade 15w-40 easily in the past, but have never been able to find Rotella T Synthetic 5w-40. I was not even aware that the Rotella T line was available in anything other than 15w-40. You guys have found synthetic 5w-40 at Wally World?
03-14-2007, 12:37 PM
#70
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Thanks Doug......... in so many ways.
03-14-2007, 12:38 PM
#71
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Looks like this sparked at good debate...
Anyway..
I dont know how many of you are driving around with oil temp gauges in your oil pan (measured at the drain plug), but i am, and on a normal 70-80'F day here in vegas it takes ages if ever for my oil to reach 170'F (80'C) during every day freeway and stop and go driving. It will in the heat of the summer thats for sure but i dont think i have ever seen it go above 190'F.
For giggles i timed the water temp yesterday...from cold start, a 75'F day and on a typical drive from my the house with a few stop lights.
This is with an aftermarket Autometer gauge tapped into the water crossover maniofld.. 1 inch from the stock sensor. I dont trust the stock gauge AT ALL now ive seen the two work side by side.
1 minute for it to come off the peg and hit the first mark at 100"f
2:30 to 150'F
3:30 to 165'F
4:30 to 180'F
5:00 to 190"f
at this point the oil temp was only just starting to come off the bottom and had not touched the first 140'F mark.
Anyway..
I dont know how many of you are driving around with oil temp gauges in your oil pan (measured at the drain plug), but i am, and on a normal 70-80'F day here in vegas it takes ages if ever for my oil to reach 170'F (80'C) during every day freeway and stop and go driving. It will in the heat of the summer thats for sure but i dont think i have ever seen it go above 190'F.
For giggles i timed the water temp yesterday...from cold start, a 75'F day and on a typical drive from my the house with a few stop lights.
This is with an aftermarket Autometer gauge tapped into the water crossover maniofld.. 1 inch from the stock sensor. I dont trust the stock gauge AT ALL now ive seen the two work side by side.
1 minute for it to come off the peg and hit the first mark at 100"f
2:30 to 150'F
3:30 to 165'F
4:30 to 180'F
5:00 to 190"f
at this point the oil temp was only just starting to come off the bottom and had not touched the first 140'F mark.
03-14-2007, 02:24 PM
#72
Under the Lift
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The likes of V300 Motul Competition 15w-50 and Castrol's 10w-60 mentioned earlier are excellent in overfuelled or carburettored engines used in (especially) long duration races
I recently read a discussion about recent changes in formulation with reduced the Zn levels in M1 and other oils as part of the SM classification. Look down this page. There is a chart and a discussion of Zn and P and boron.
http://www.lnengineering.com/oil.html
Are you concerned about the reduction in Zn? If you already have commented, I will search for it. I gather the deisel oils still have high Zn levels.
I was wondering how you thought the Castrol 10W-60 might perform in our cars, if they are stressed periodically by high speed, high heat driving, like mine is.
03-14-2007, 02:38 PM
#73
Rennlist Member
Originally Posted by Bill Ball
My 89 is almost entirely used on the street, but then there are those 3-4 open road races I do with it. These are 100 miles at 145+ MPH average speed in desert heat at 5000 feet. The car seems to do fine on M1. No known issues at 178k miles. I had low oil pressure at idle when I came to a stop at then end of one race when I had 5W-40 Castrol synthetic in the car, installed thinking the 5W might be better for start up wear. The 40W did not seem up to the desert heat and high speed. So, I went back to M1.
I recently read a discussion about recent changes in formulation with reduced the Zn levels in M1 and other oils as part of the SM classification. Look down this page. There is a chart and a discussion of Zn and P and boron.
http://www.lnengineering.com/oil.html
Are you concerned about the reduction in Zn? If you already have commented, I will search for it. I gather the deisel oils still have high Zn levels.
I was wondering how you thought the Castrol 10W-60 might perform in our cars, if they are stressed periodically by high speed, high heat driving, like mine is.
I recently read a discussion about recent changes in formulation with reduced the Zn levels in M1 and other oils as part of the SM classification. Look down this page. There is a chart and a discussion of Zn and P and boron.
http://www.lnengineering.com/oil.html
Are you concerned about the reduction in Zn? If you already have commented, I will search for it. I gather the deisel oils still have high Zn levels.
I was wondering how you thought the Castrol 10W-60 might perform in our cars, if they are stressed periodically by high speed, high heat driving, like mine is.
The new SM formulation of Mobil 1 15w50 seems to have in addition to reducing the Zn and P significantly, they also reduced the boron from 226ppm to 72ppm and eliminated all trace of sodium and magnesium, two other known anti-wear additives. It would look like it's an entirely new formulation than the SL it's replacing. I strongly recommend those running Mobil 1 15w50 switch to Mobil 1 V-Twin 20w50, which still is an API SG oil, which has the highest level of zinc found in any motor oil, which adding the boron at levels typically only seen in low Zn and P formulations. This should technically provide the best protection in my opinion. We will be testing their 10w40 4T Racing Motorcycle Mobil 1 formulation to see if it is similar.
03-14-2007, 03:00 PM
#74
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Originally Posted by Gretch
Thanks Doug......... in so many ways.
Thank you.
03-14-2007, 03:05 PM
#75
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Originally Posted by hupp
I've been able to find Shell Rotella T Multi Grade 15w-40 easily in the past, but have never been able to find Rotella T Synthetic 5w-40. I was not even aware that the Rotella T line was available in anything other than 15w-40. You guys have found synthetic 5w-40 at Wally World?