why do people mess with the OMP?
#76
I'm a boost creep...
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I based my decision to premix on comments I read from well regarded engine builders on the cleanliness of a premixed vs oil injected engine - that a 20k motor run with the engine oil system was fairly dirty inside (carbon buildup), and a 20k motor run on premix was still almost new looking inside.
Also, the Mazda race teams premix (apparently richer than 50:1 in many cases). If that's not evidence that premixing is better for the engine, I don't know what is.
#78
Clean.
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Better clear some things up...
Your engine can last plenty long with the stock setup. Premixing is to further reduce wear and improve sealing. Basically you are using an oil more specifically designed for the specific application, instead of Mazda's approach of using the oil that's more convenient and still works well enough.
Right now I'm debating on which to do first: get the OMP adaptor to feed in 2-stroke oil, or get a bypass oil filter (100% filtration; common on 18 wheelers, I think). Why? B/c I'm ****. It's really not necessary, but I'd like my engine to last even longer.
Someone mentioned oil being injected into the intake too, not just the housings. What do you mean? The intake air? The gasoline?
- 4 stroke oil might mix fine with gas, but it just isn't specifically designed to lubricate a combustion chamber and be burned. Still works well enough though. Certain synthetic 4-stroke oils supposedly leave excessive deposits when burned, hence all the hooha about them. Heck, some people run diesel oil in their non-diesel cars. That isn't ideal either, but it works okay (they do it for the extra detergent levels, but it isn't recommended due to formulation differences).
- People who rebuild engines notice less wear near the oil injectors, more elsewhere. That's one reason to premix.
- The OMP adjusts oil based on throttle. Racers are always at full throttle and usually want extra lube, so they just premix and ditch the OMP.
- Premixing uses more oil. Partly b/c the OMP adjusts oil based on throttle, whereas you need to premix enough to protect at 100% throttle. The rest of the time the extra oil is wasted. I think it's also b/c when you premix more oil is burnt before ever hitting the walls. And it's more trouble. But it's cheaper. An OMP on a weedwacker would be too expensive.
Your engine can last plenty long with the stock setup. Premixing is to further reduce wear and improve sealing. Basically you are using an oil more specifically designed for the specific application, instead of Mazda's approach of using the oil that's more convenient and still works well enough.
Right now I'm debating on which to do first: get the OMP adaptor to feed in 2-stroke oil, or get a bypass oil filter (100% filtration; common on 18 wheelers, I think). Why? B/c I'm ****. It's really not necessary, but I'd like my engine to last even longer.
Someone mentioned oil being injected into the intake too, not just the housings. What do you mean? The intake air? The gasoline?
Last edited by ericgrau; 07-21-07 at 11:02 PM.
#80
Lives on the Forum
So much bullshit comes out from both sides, it's not even funny.
Engine oil wasn't designed to be "injected" into the engine and burned.
Premix was designed to be mixed with fuel and "injected" into the engine and used as internal lubrication.
Period.
This should be end of discussion.
Mazda's official stance is that they didn't want to add another fluid system that needed to be topped off every month or so to add complexity to the vehicle - the stock oil injection is a compromise system.
Period.
Even with the above evidence, people are still going to debate it.
It's funny how some of the most adamant arguments are coming from people who have never tried both (or more accurately, premixing).
-Ted
#81
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The fact of the matter is, a rotary engine should have run premix from the start, but selling a car that need to get oil in the tank while you fill up would not have been a great seller, so mazda had to find a way to mix oil in the cumbustion chamber without any hassle for the owner...hence, the omp.
#85
I'm a boost creep...
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There hasn't been any actual evidence presented here. Just a lot of "I think..." and I believe..."
I don't/won't premix for exactly the reason Mazda designed the OMP system. I can't think of anything I'd want to do less than have to add oil with every gas fill.
Do I think 2-stroke oil is a better chamber lubricant than normal engine oil? Sure.
Do I think premixing is an inherently better method of chamber lubrication? Nope.
Do I drive around thinking I'm damaging my engine? Nope.
Do I really think I'm going to significantly extend the life of an engine that usually fails because of something unrelated to chamber lubrication? Nope.
Like Hailers said, you're all paranoid.
It's funny how some of the most adamant arguments are coming from people who have never tried both (or more accurately, premixing).
Do I think 2-stroke oil is a better chamber lubricant than normal engine oil? Sure.
Do I think premixing is an inherently better method of chamber lubrication? Nope.
Do I drive around thinking I'm damaging my engine? Nope.
Do I really think I'm going to significantly extend the life of an engine that usually fails because of something unrelated to chamber lubrication? Nope.
Like Hailers said, you're all paranoid.
#87
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On s5's I have heard about the OMP failing. Again, I don't really have enough experience to say the do or don't fail, or that they are inferior.
Not wanting to start **** RotaMan99, but calling everyone paranoid about the OMP system is rediculous. I can understand why people would be paranoid about it, you're talking about a system that's nearly 20 years old.
I feel safer trusting the pre-mix I put in the gas tank than trusting the injectors
pump
and vacuum lines.
Im surprised you said nothing about the OMP lines. If you still have the original lines, I would replace them, then don't worry about them for another 15+ years.
You have no easy way of telling that the system is working correctly
Another reason for pre-mixing is obviously the cleaner burn that it creates. It's been show many times that a pre-mixed engines come out with less carbon buildup than what the OMP run cars do.
IMO, there is still no reason to argue over this topic. It's been shown MANY MANY MANY times over now the reasons for choose either system. Please, do a search and read the FAQ's. It's been covered.
#88
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Yep, no wonder these things get locked...
So much bullshit comes out from both sides, it's not even funny.
Engine oil wasn't designed to be "injected" into the engine and burned.
Premix was designed to be mixed with fuel and "injected" into the engine and used as internal lubrication.
Period.
This should be end of discussion.
Mazda's official stance is that they didn't want to add another fluid system that needed to be topped off every month or so to add complexity to the vehicle - the stock oil injection is a compromise system.
Period.
Even with the above evidence, people are still going to debate it.
It's funny how some of the most adamant arguments are coming from people who have never tried both (or more accurately, premixing).
So much bullshit comes out from both sides, it's not even funny.
Engine oil wasn't designed to be "injected" into the engine and burned.
Premix was designed to be mixed with fuel and "injected" into the engine and used as internal lubrication.
Period.
This should be end of discussion.
Mazda's official stance is that they didn't want to add another fluid system that needed to be topped off every month or so to add complexity to the vehicle - the stock oil injection is a compromise system.
Period.
Even with the above evidence, people are still going to debate it.
It's funny how some of the most adamant arguments are coming from people who have never tried both (or more accurately, premixing).
#89
No rotary, no problems?
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Besides that, explain to me what the disadvantages to pre-mixing are besides the obvious of actually having to get off your *** to pour the oil in the gas tank (c'mon people...). I can tell you numerous disadvantages to the OMP....
#90
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I wouldn't call it paranoid. I'd call it logical.
Premix was made to lubricate and burn off, not engine oil.
#91
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Please don't tell me that you're saying Ted doesn't know how something works on the RX-7...
He obveously doesn't. Let me quote what he wrote.
It's the OIL INJECTORS that fail.
They're supposed to have a built-in check valve that supposed to keep the oil in the oil injector / lines at all times.
Once that check valve fails, air gets into the lines, and you get periods where no oil is injected into the engine.
I've purchased brand new oil injectors that have FAILED in under 10,000 miles.
They're supposed to have a built-in check valve that supposed to keep the oil in the oil injector / lines at all times.
Once that check valve fails, air gets into the lines, and you get periods where no oil is injected into the engine.
I've purchased brand new oil injectors that have FAILED in under 10,000 miles.
I bet he doesn't even know EXACTLY how the OMP works and why it works the way it does. Im sure you don't either along with the many paranoid people in this thread.
Besides that, explain to me what the disadvantages to pre-mixing are besides the obvious of actually having to get off your *** to pour the oil in the gas tank (c'mon people...). I can tell you numerous disadvantages to the OMP....
Tell me you have ACTUAL disadvantages of the OMP instead of your own asumptions.
#92
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or get a bypass oil filter (100% filtration; common on 18 wheelers, I think).
http://www.amsoil.com/StoreFront/eabp.aspx
I would use a full flow oil filter, plus the bypass system. Thats just me though.
#93
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The problem is that not all the oil that gets sumped will be filtered but does eventually get all the oil. But does filter much more then full flow oil filters
http://www.amsoil.com/StoreFront/eabp.aspx
I would use a full flow oil filter, plus the bypass system. Thats just me though.
http://www.amsoil.com/StoreFront/eabp.aspx
I would use a full flow oil filter, plus the bypass system. Thats just me though.
#94
Lives on the Forum
Wow, that's interesting...
Since when does the oil injectors have anything to do with the compression cycle?
The rotor (face) starts the compression cycle from the 12 o'clock position to the 3 o'clock position.
The majority of the compression cycle is after the rotor (face) has past the (stock) intake port.
The oil injectors are in the intake port, so tell me how you can talk about oil injectors and compression at the same time?
Wow, I guess I should throw away all my SAE papers on the subject then and just ask you...?
Oh, another thing...
All Mazda sponsored factory race cars have run pre-mix.
None of them use anything that resembles the stock oil injection system.
-Ted
Its during the compression on Turbo motors when the check valve comes in handy,
The rotor (face) starts the compression cycle from the 12 o'clock position to the 3 o'clock position.
The majority of the compression cycle is after the rotor (face) has past the (stock) intake port.
The oil injectors are in the intake port, so tell me how you can talk about oil injectors and compression at the same time?
I bet he doesn't even know EXACTLY how the OMP works and why it works the way it does. Im sure you don't either along with the many paranoid people in this thread.
Oh, another thing...
All Mazda sponsored factory race cars have run pre-mix.
None of them use anything that resembles the stock oil injection system.
-Ted
#95
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Since when does the oil injectors have anything to do with the compression cycle?
Oh, another thing...
All Mazda sponsored factory race cars have run pre-mix.
None of them use anything that resembles the stock oil injection system.
All Mazda sponsored factory race cars have run pre-mix.
None of them use anything that resembles the stock oil injection system.
Wow, I guess I should throw away all my SAE papers on the subject then and just ask you...?
If you are relying on them for that information, then yes throw them away.
#96
i quote........
The oil nozzle has a one-way check valve witch acts as an air bleed to prevent excessive suction of oil and to atomize the oil.
When vacuum is created in the combustion chamber and intake manifold during the suction period, the check valve is pulled open and allows air to mix with the oil. During the compression period, pressure is applied and the valve closes to prevent back flow of oil into the connecting hose.
....just thought id throw that out there.
...they arent vacuum lines.
you cant ignore the reliability of premixing (if you are responsible enough to do it all the time). if i needed 100% reliability i would rather not trust a mechanical device. regardless if the injector fails or the omp fails, the system may still fail.
The oil nozzle has a one-way check valve witch acts as an air bleed to prevent excessive suction of oil and to atomize the oil.
When vacuum is created in the combustion chamber and intake manifold during the suction period, the check valve is pulled open and allows air to mix with the oil. During the compression period, pressure is applied and the valve closes to prevent back flow of oil into the connecting hose.
....just thought id throw that out there.
The check valve closes so the compressed air does not force oil back through the vacuum lines and into the TB or intake, where ever the vacuum spider is connected..
you cant ignore the reliability of premixing (if you are responsible enough to do it all the time). if i needed 100% reliability i would rather not trust a mechanical device. regardless if the injector fails or the omp fails, the system may still fail.
#97
Lives on the Forum
The use of the word "compression" is being used in the wrong context then.
If you're just talking about turbo motors, why does Mazda use the same part number for turbo and non-turbo FC's?
What about the oil pressure that's coming through the oil injectors?
Isn't that enough oil pressure to counteract the stock 5.5psi and 7.5psi of boost any stock FC turbo would see?
Which just proves my point about compromise...
If we're trying to design BEST lubrication, then racing conditions would simulate what the worse abuse the engine would see.
Premixing is Mazda's answer to what severe duty engine conditions would produce.
This shows your ignorance on the subject.
I'm sure SAE International would take you seriously...
http://www.sae.org/
-Ted
The check valve closes so the compressed air does not force oil back through the vacuum lines and into the TB or intake, where ever the vacuum spider is connected..
What about the oil pressure that's coming through the oil injectors?
Isn't that enough oil pressure to counteract the stock 5.5psi and 7.5psi of boost any stock FC turbo would see?
And what is your point? Mazda designed the oil injecton system for the what the car is built for. It was not built for hi end racing. If you can modify the OMP system to inject 2 stroke, that would be best.
If we're trying to design BEST lubrication, then racing conditions would simulate what the worse abuse the engine would see.
Premixing is Mazda's answer to what severe duty engine conditions would produce.
I have never seen any SAE papers telling you how the OMP system works and why the OMP works the way it does or how the injectors are designed and why they are designed that way.
If you are relying on them for that information, then yes throw them away.
http://www.sae.org/
-Ted
#98
drifting is an artform
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Haha, this is great... I'm learning so much.
Ted, your my hero.
*edit* yo bro, I'm on Oahu till the 3rd, currently in waikiki, anything to do automobile wise around here?
Ted, your my hero.
*edit* yo bro, I'm on Oahu till the 3rd, currently in waikiki, anything to do automobile wise around here?
#99
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The use of the word "compression" is being used in the wrong context then.
...they arent vacuum lines.
you cant ignore the reliability of premixing (if you are responsible enough to do it all the time). if i needed 100% reliability i would rather not trust a mechanical device. regardless if the injector fails or the omp fails, the system may still fail.
you cant ignore the reliability of premixing (if you are responsible enough to do it all the time). if i needed 100% reliability i would rather not trust a mechanical device. regardless if the injector fails or the omp fails, the system may still fail.
I quote........
The oil nozzle has a one-way check valve witch acts as an air bleed to prevent excessive suction of oil and to atomize the oil.
When vacuum is created in the combustion chamber and intake manifold during the suction period, the check valve is pulled open and allows air to mix with the oil. During the compression period, pressure is applied and the valve closes to prevent back flow of oil into the connecting hose.
....just thought id throw that out there.
The oil nozzle has a one-way check valve witch acts as an air bleed to prevent excessive suction of oil and to atomize the oil.
When vacuum is created in the combustion chamber and intake manifold during the suction period, the check valve is pulled open and allows air to mix with the oil. During the compression period, pressure is applied and the valve closes to prevent back flow of oil into the connecting hose.
....just thought id throw that out there.
The term vacuum lines is a universal term I use for the "small rubber hoses" that are on the engine supplying vacuum or metered air.
If you're just talking about turbo motors, why does Mazda use the same part number for turbo and non-turbo FC's?
What about the oil pressure that's coming through the oil injectors?
Isn't that enough oil pressure to counteract the stock 5.5psi and 7.5psi of boost any stock FC turbo would see?
Isn't that enough oil pressure to counteract the stock 5.5psi and 7.5psi of boost any stock FC turbo would see?
Which just proves my point about compromise...
If we're trying to design BEST lubrication, then racing conditions would simulate what the worse abuse the engine would see.
Premixing is Mazda's answer to what severe duty engine conditions would produce.
If we're trying to design BEST lubrication, then racing conditions would simulate what the worse abuse the engine would see.
Premixing is Mazda's answer to what severe duty engine conditions would produce.
Im sure their engines also produce a lot more HP, a lot more heat and rev much higher then ours.
This shows your ignorance on the subject.
I'm sure SAE International would take you seriously...
http://www.sae.org/
http://www.sae.org/
Haha, this is great... I'm learning so much.
Ted, your my hero.
Ted, your my hero.
#100
Lives on the Forum
So you're claiming there is absolutely no pressure in the oil injection system?
How does the oil get from the OMP to the oil injectors?
Pure vacuum?
What about turbo engines?
How do you draw oil into the engine if there is pressure in the intake?
So if it's vacuum drawing the oil into the engine, then a turbo motor would not be injecting oil into the engine under boost?
How about a non-turbo engine at WOT?
At that point, the "pressure" in the intake is "0", so if the system needs vacuum to operate, a non-turbo engine will have no oil injected at WOT!
Ludicrous...
So there has to be SOME pressure in the oil injection system...
-Ted