Synthetic Oil Study, interesting....
#31
Heres one way to explain oil.
conventional oil molecules look something like this:
.oO.0o()..0o. (pay attention to the idea lol)
The molecules are all different sizes.
conventional oils break down and after a while:
ooo..........
sooo the oil provides less protection because it breaks down from use.
The idea of synthetic oil is that the molecules are the perfect size and stay the same size even after use:
ooooooooo
Technically synthetic oil should never have to be replaced. Syn just gets contaminated, it doesnt go bad.
Infact, Amsoil has their own filtration system that uses 2 of t heir own oil filters. They gaurentee that their oil will last for 100,000 miles without ever having to be changed. You do however have to replace the filter every 15k i believe it was. You do have to add a little bit of oil to compensate for the loss of the oil containted in the filters.
Normal synthetic recomends oil changes every 5k, Amsoil recommends 7.5k or 12k if using their filter.
conventional oil molecules look something like this:
.oO.0o()..0o. (pay attention to the idea lol)
The molecules are all different sizes.
conventional oils break down and after a while:
ooo..........
sooo the oil provides less protection because it breaks down from use.
The idea of synthetic oil is that the molecules are the perfect size and stay the same size even after use:
ooooooooo
Technically synthetic oil should never have to be replaced. Syn just gets contaminated, it doesnt go bad.
Infact, Amsoil has their own filtration system that uses 2 of t heir own oil filters. They gaurentee that their oil will last for 100,000 miles without ever having to be changed. You do however have to replace the filter every 15k i believe it was. You do have to add a little bit of oil to compensate for the loss of the oil containted in the filters.
Normal synthetic recomends oil changes every 5k, Amsoil recommends 7.5k or 12k if using their filter.
#32
We've been looking at things from a reliability angle, but isn't it an accepted axiom that newer engine oil gives a car more power as compared to oil that has been in it for, say, 20K miles? At least that's what the butt dyno tells me. Anyone who actually knows care to shed some light on this?
#35
Originally posted by Creamo3
This info. is interesting indeed, it must be the oil companies that are recommending such low mileage to change at in order to make their money. Conspiracy Theory
This info. is interesting indeed, it must be the oil companies that are recommending such low mileage to change at in order to make their money. Conspiracy Theory
#36
Originally posted by superz
Very informative study, however we must remember that a low revving, low cylinder pressure, high torque(at very low rpms) V8 engine can hardly be compared to an Evo engine. We deal with 135.5 hp per liter to start with. The 5.7 liter in the study car would have to produce 772.35 hp to equal the amount of stress that our engines go through. Our Evo's, like mine, can easily produce 400 crankshaft hp (with stock internals) with few mods. At this rate the GM 5.7 liter would have to produce 1140hp to equal the stress of our little 2 liter!!!!! . At that stress level (and high rpm's needed to get there) our 2.0 will produce more blow-by, more wear on metal surfaces, more heat that WILL dramatically reduce the life of synthetic oil. If you read the reports they claim a syrup like color when they rechecked the oil at intervals. My oil looks BLACK at like 1500 after changing the oil. After being a technician for over 8 years I have never seen a turbocharged car's engine oil look any different after very low mileage. Its completely normal for those that really drive their cars the way they were meant to be driven. I always suggest changing the oil at no more than 3500 miles, less if you can afford it.
Very informative study, however we must remember that a low revving, low cylinder pressure, high torque(at very low rpms) V8 engine can hardly be compared to an Evo engine. We deal with 135.5 hp per liter to start with. The 5.7 liter in the study car would have to produce 772.35 hp to equal the amount of stress that our engines go through. Our Evo's, like mine, can easily produce 400 crankshaft hp (with stock internals) with few mods. At this rate the GM 5.7 liter would have to produce 1140hp to equal the stress of our little 2 liter!!!!! . At that stress level (and high rpm's needed to get there) our 2.0 will produce more blow-by, more wear on metal surfaces, more heat that WILL dramatically reduce the life of synthetic oil. If you read the reports they claim a syrup like color when they rechecked the oil at intervals. My oil looks BLACK at like 1500 after changing the oil. After being a technician for over 8 years I have never seen a turbocharged car's engine oil look any different after very low mileage. Its completely normal for those that really drive their cars the way they were meant to be driven. I always suggest changing the oil at no more than 3500 miles, less if you can afford it.
The point of the study was that while your oil is black at 1500 miles, the oil isn't degrading significantly more in the next 6000 or 9000 miles. Thus, changing it at 1500 and 10000 would have the same overall effect. As an example, a friend sent in his 7500 mile old Mobil 1 out of a supercharged S2000 (425 crank hp give or take, or roughly 210/L), and the analysis indicated the oil had a considerable amount of usable life left - even though it was black.
Ultimately, the best thing you can do is follow your owners manual while the car is still in warranty. If it says 7500, do it every 7500, and if the proverbial **** hits the fan, you just followed their recommendations and are in the clear. After the warranty is up, less often is alright.
#37
Originally posted by WestSideBilly
What's going on inside the cylinders has very little effect on the oil, except in the case of blowby. Using your logic of specific output equaling stress levels, a turbodiesel with 30 hp/L would have no stress - despite the 18.5:1 compression. This isn't the case.
The point of the study was that while your oil is black at 1500 miles, the oil isn't degrading significantly more in the next 6000 or 9000 miles. Thus, changing it at 1500 and 10000 would have the same overall effect. As an example, a friend sent in his 7500 mile old Mobil 1 out of a supercharged S2000 (425 crank hp give or take, or roughly 210/L), and the analysis indicated the oil had a considerable amount of usable life left - even though it was black.
Ultimately, the best thing you can do is follow your owners manual while the car is still in warranty. If it says 7500, do it every 7500, and if the proverbial **** hits the fan, you just followed their recommendations and are in the clear. After the warranty is up, less often is alright.
What's going on inside the cylinders has very little effect on the oil, except in the case of blowby. Using your logic of specific output equaling stress levels, a turbodiesel with 30 hp/L would have no stress - despite the 18.5:1 compression. This isn't the case.
The point of the study was that while your oil is black at 1500 miles, the oil isn't degrading significantly more in the next 6000 or 9000 miles. Thus, changing it at 1500 and 10000 would have the same overall effect. As an example, a friend sent in his 7500 mile old Mobil 1 out of a supercharged S2000 (425 crank hp give or take, or roughly 210/L), and the analysis indicated the oil had a considerable amount of usable life left - even though it was black.
Ultimately, the best thing you can do is follow your owners manual while the car is still in warranty. If it says 7500, do it every 7500, and if the proverbial **** hits the fan, you just followed their recommendations and are in the clear. After the warranty is up, less often is alright.
#39
For those trying to compare engine output to stress on the motor. You're all way off. The torque the motor generates is usually equally generated across each cylinder. 300 ft lbs of torque in a 4 cylinder is equal to 75 ftlbs of torque, that torque is force first generated by the piston moving down and pushing a rod against the oil that pushes against the crank. The oil needs to remain in place against that pressure. so a V8 would have to endure 600 ftlbs of torque to simulate the pressure the oils in a typical Evo endures.
But back to the oil itself. I frequently in all my cars let the oil "age". Fresh filter and oil each change usually around 6 - 8k miles. and I drive it like I stole it too often. Amsoil has always netted me the best hp on the dyno and like studies show synthetics really only break down when literally cooked as some turbos can do. Other times it's just contaminants getting in from blowby, or some other peculiar means, leaks, open dipstick, letting bugs crawl in the valve cover oil opening.. etc..
But back to the oil itself. I frequently in all my cars let the oil "age". Fresh filter and oil each change usually around 6 - 8k miles. and I drive it like I stole it too often. Amsoil has always netted me the best hp on the dyno and like studies show synthetics really only break down when literally cooked as some turbos can do. Other times it's just contaminants getting in from blowby, or some other peculiar means, leaks, open dipstick, letting bugs crawl in the valve cover oil opening.. etc..
#40
Newbie
Joined: Nov 2003
Posts: 66
Likes: 0
From: West Texas, where the roads are straight and long, and the law is few and far between
Originally posted by Mister2zx3
For those trying to compare engine output to stress on the motor. You're all way off. The torque the motor generates is usually equally generated across each cylinder. 300 ft lbs of torque in a 4 cylinder is equal to 75 ftlbs of torque, that torque is force first generated by the piston moving down and pushing a rod against the oil that pushes against the crank. The oil needs to remain in place against that pressure. so a V8 would have to endure 600 ftlbs of torque to simulate the pressure the oils in a typical Evo endures.
For those trying to compare engine output to stress on the motor. You're all way off. The torque the motor generates is usually equally generated across each cylinder. 300 ft lbs of torque in a 4 cylinder is equal to 75 ftlbs of torque, that torque is force first generated by the piston moving down and pushing a rod against the oil that pushes against the crank. The oil needs to remain in place against that pressure. so a V8 would have to endure 600 ftlbs of torque to simulate the pressure the oils in a typical Evo endures.
#41
Certainly, it does get more techinical with load areas and such, but a brief high level there was just to point out horsepower is not a big factor, unless used to find the torque to get down to the psi excerted on some particular engine location.
As for torque distribution across cylinders, it's usually within a percent or two of each other for force generated. As the crank goes through it's rotation from the point of force generation (Piston forced down) till the next cylinder becomes the "pusher" there is some arc, so it's not linear, but at across it's average while under it's portion rotation generating power, it should be pretty close to the torque / # of cylinders. There are finer details, but the max torque per rod usually is not more than 15% of that and those are usually low speed, high load situations.
As for torque distribution across cylinders, it's usually within a percent or two of each other for force generated. As the crank goes through it's rotation from the point of force generation (Piston forced down) till the next cylinder becomes the "pusher" there is some arc, so it's not linear, but at across it's average while under it's portion rotation generating power, it should be pretty close to the torque / # of cylinders. There are finer details, but the max torque per rod usually is not more than 15% of that and those are usually low speed, high load situations.
#42
Originally posted by superz
Very informative study, however we must remember that a low revving, low cylinder pressure, high torque(at very low rpms) V8 engine can hardly be compared to an Evo engine. We deal with 135.5 hp per liter to start with. The 5.7 liter in the study car would have to produce 772.35 hp to equal the amount of stress that our engines go through. Our Evo's, like mine, can easily produce 400 crankshaft hp (with stock internals) with few mods. At this rate the GM 5.7 liter would have to produce 1140hp to equal the stress of our little 2 liter!!!!! . At that stress level (and high rpm's needed to get there) our 2.0 will produce more blow-by, more wear on metal surfaces, more heat that WILL dramatically reduce the life of synthetic oil. If you read the reports they claim a syrup like color when they rechecked the oil at intervals. My oil looks BLACK at like 1500 after changing the oil. After being a technician for over 8 years I have never seen a turbocharged car's engine oil look any different after very low mileage. Its completely normal for those that really drive their cars the way they were meant to be driven. I always suggest changing the oil at no more than 3500 miles, less if you can afford it.
Very informative study, however we must remember that a low revving, low cylinder pressure, high torque(at very low rpms) V8 engine can hardly be compared to an Evo engine. We deal with 135.5 hp per liter to start with. The 5.7 liter in the study car would have to produce 772.35 hp to equal the amount of stress that our engines go through. Our Evo's, like mine, can easily produce 400 crankshaft hp (with stock internals) with few mods. At this rate the GM 5.7 liter would have to produce 1140hp to equal the stress of our little 2 liter!!!!! . At that stress level (and high rpm's needed to get there) our 2.0 will produce more blow-by, more wear on metal surfaces, more heat that WILL dramatically reduce the life of synthetic oil. If you read the reports they claim a syrup like color when they rechecked the oil at intervals. My oil looks BLACK at like 1500 after changing the oil. After being a technician for over 8 years I have never seen a turbocharged car's engine oil look any different after very low mileage. Its completely normal for those that really drive their cars the way they were meant to be driven. I always suggest changing the oil at no more than 3500 miles, less if you can afford it.
#43
Newbie
Joined: Nov 2003
Posts: 66
Likes: 0
From: West Texas, where the roads are straight and long, and the law is few and far between
Originally posted by Mister2zx3
Certainly, it does get more techinical with load areas and such, but a brief high level there was just to point out horsepower is not a big factor, unless used to find the torque to get down to the psi excerted on some particular engine location.
As for torque distribution across cylinders, it's usually within a percent or two of each other for force generated. As the crank goes through it's rotation from the point of force generation (Piston forced down) till the next cylinder becomes the "pusher" there is some arc, so it's not linear, but at across it's average while under it's portion rotation generating power, it should be pretty close to the torque / # of cylinders. There are finer details, but the max torque per rod usually is not more than 15% of that and those are usually low speed, high load situations.
Certainly, it does get more techinical with load areas and such, but a brief high level there was just to point out horsepower is not a big factor, unless used to find the torque to get down to the psi excerted on some particular engine location.
As for torque distribution across cylinders, it's usually within a percent or two of each other for force generated. As the crank goes through it's rotation from the point of force generation (Piston forced down) till the next cylinder becomes the "pusher" there is some arc, so it's not linear, but at across it's average while under it's portion rotation generating power, it should be pretty close to the torque / # of cylinders. There are finer details, but the max torque per rod usually is not more than 15% of that and those are usually low speed, high load situations.
what I meant by the linearity comment was just that the effective pressure exerted on a particular engine contact surface by 75hp per cyl in a 4-cyl engine wouldn't necessarily be equivalent to the effective pressure exerted by 75hp on the "same" engine contact surface in an 8-cyl engine, which is what I thought you implied...