NZConvertible

Where these identical engines with identical fuelling systems driven in an identical manner? Highly unlikely. The problem with most "proof" of the superiority of premix is that is doesn't even come close to the level of proof required in any field of engineering or science. There's plenty of anecdotal evidence of the type you just gave and there's also some contradictory anecdotal evidence too.

It doesn't prove that at all. It's evidence of typical race car engineering where simplicity is far more important. Mazda don't make "race" OMP systems, and there'd be no benefit to teams trying to develop there own. If these teams feel the need to use such rich oil mixtures then a stock OMP is not going to provide that.

TehMonkay

iTrader: (-1)

No test no proof.

ericgrau

iTrader: (1)

Better clear some things up...

• 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?

unW7WZ

there are 4 oil injectors, 2 in the housings and 2 in the LIM.

RETed

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).


-Ted

Spectator

iTrader: (1)

But it wasn't...eventhough I answered on post #2

RETed

Don't we all sound like a broken record?
Bashing out heads against the wall?



-Ted

ericgrau

iTrader: (1)

What's the LIM?

MaczPayne

iTrader: (5)

LIM = Lower intake manifold

NZConvertible

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.

Spectator

iTrader: (1)

I wouldn't call it paranoid. I'd call it logical.

Use a product for what its designed for. Dont recycle it someother way.

Premix was made to lubricate and burn off, not engine oil.

RotaMan99

Thats due to the electronics. The internal mechanics are slightly different then the S4 but I don't think that the s5 mechanically it would go wrong.

It's rediculous? Untill you open up a S4 mech omp, and UNDERSTAND EXACTLY how it works, don't says that people should be worried it will fail.

They can't fail to the point where that don't inject oil. Unles you don't do the maintenance and keep the oil dirty so they have the potential of clogging.

Read what I wrote above

This is part of the maintenance that you are supposed to do on your vehical. If your vac lines brake or crack, you will have a vacuum leak and your injectors will still work perfectly fine.

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.

Sure you do, pull the lines off and watch for oil flowing out. You can even measure how many CC's flow in I think its 5 minutes the FSM says.

I don't doubt that, this debate is not about whether to premix or not. Its about the OMP system in general.

If its been covered why are you pointing out areas in the OMP system that you say could fail and will ruin your engine that actually wont fail and ruin your engine.

RotaMan99

Its funny you are saying this since you have no idea how the system actually works.

Ice_Wolf

Please don't tell me that you're saying Ted doesn't know how something works on the RX-7...

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....

RotaMan99

Read what I wrote above about knowing exactly how the OMP works.

2 stroke is made to burn clean. Premix is a term used to describe 2 stroke mixed with gasoline.

RotaMan99

You saying what he said below is correct?

He obveously doesn't. Let me quote what he wrote.
Thats NOT how the injectors work and thats NOT why there is a check valve and thats NOT where the check valve is. If the check valve fails the oil will STILL flow through the injector and the injector will work PERFECTLY fine. Its during the compression on Turbo motors when the check valve comes in handy, otherwise the oil could get blown back through the vaccum lines and through the TB.

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.

You need to read the whole thread and not skim through. I can't list ANY performance disadvantages for premix. I never said premix was bad or its worse then motor oil, I have been saying why use it in high millage engines to expect any difference at all? I premixed my engine for 4 years starting at around 130K miles. It blew at 168K.

Tell me you have ACTUAL disadvantages of the OMP instead of your own asumptions.

RotaMan99

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.

RotaMan99

I don't know why I said what I said. Because thats exactly how it works. Ima dumby.

RETed

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

RotaMan99

Im talking about when the intake air is compressed as in boost. 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..

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.

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.

imloggedin

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.

RETed

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

fc.fanatic

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?

RotaMan99

How is this? How about if I say, the compression period?

Why throw this out there? Guess what that connecting hose is?

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.

Ask them, im sure its cheaper to mass produce one item then 2 different ones that do the same job. You trying to say that how I say they operate, is not the way they operate?

hahaha. There is NO PRESSURE in the OMP Lines. Wow, I can't believe you just said that.

That doesn't prove anything.
Im sure their engines also produce a lot more HP, a lot more heat and rev much higher then ours.

It goes to show that you don't know how the OMP system works but yet you keep spreading mis information.

Show me where they tell you how our system works.

If you are learning something from Ted and he is your hero, you are not learning how the omp system correctly works.

RETed

Be careful what you say...

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