TZ250

Thanks. I'm pretty familiar with the generalities. I have found all the oil discussion very interesting because I'm new. I have read all the oil threads start to finish. Definitely OCD. I know many of you have been talking about this stuff for years. It's a genuine 6 year food fight.

Anyway, I'm looking for a specific response to my question, if you know. You made a generalized statement about viscosity and cavitation, and I would like to know if the statement applies to the oil temp in the engine, or at the babbit/journal interface. As you said, they are not the same.

dannobre

iTrader: (3)

The temp would be of the oil.......the testing parameters are external.....

I reality the actual oil temps at each point in the engine are unlikely to be known without generalities...so to say conclusively what is going on is way past my knowledge base

I wouldn't think the delta's at bearings and such will be that different in different engines that the generalities wouldn't be relevant

You can spend weeks on BITOG and other oil forums and still be confused

TZ250

I went and found the source of dannobre's quote. The guy is a chemist for Fuchs/Silkolene. I found this quote very interesting too.

"The type of oil that is likely to give trouble after low mileage is a light viscosity type with poor shear stability, either mineral or modified mineral based. (Such as one of the USA ‘fuel economy’ oils for lazy car engines that pushed the Japanese OEMs to bring in their own oil spec.) The important thing is the shear stability; the much hyped ‘synthetic or mineral’ nonsense is a red herring."

Here is the link if you want to read the post.

http://www.bobistheoilguy.com/forums...Number=1643123

nycgps

iTrader: (1)

funny thing is on paper stuff might fail in real life. regardless of how wonderful/right it might be.

Renesis wear is a Perfect example.

Flashwing

Sure, because physics and fluid dynamics are totally different on paper than they are in reality. That makes total sense.

I don't know if I'd call it a red herring but again this comment is right on the money with the overall shear stability being important. It's all a balance act and being realistic about your application will help you make the right choice. It comes down to oil that flows the best both cold (for startup protection) and during operational temperature while providing the necessary shear protection and barrier additives to keep metal parts protected.

nycgps

iTrader: (1)

I also know 5w20 running engines are failing. and its not just Rotary, damn.

Yes they offer enough protection ... Until warranty is up ?

9krpmrx8

iTrader: (46)

Good article. More good stuff on 0W for everyday use.

9krpmrx8

iTrader: (46)

That' s a pretty broad statement man. Again, the oil type is not the lone cause of failures NYCGPS. And my dad has run 5W-20 in his Miata for years. It all depends how you drive and how you maintain it.

nycgps

iTrader: (1)

well, you can say that but ...

shouldn't we be using an oil that can protect us all the time "regardless" of how we drive it ?

Yes I know the more aggressive we drive, more wear the car will get ... argh, know what I mean ?

at least with heavier oil, we will have one "less" problem to worry about.

You see the whole point of this thread (my personal opinion) is that with everything else stock (pump, pressure, whatever), 5w30 dont cut it. Something heavier should be used.

Mazda increased the pressure on S2, does it work? I dont know. Is it just because of the light oil weight? I would say 50/50. Dont forget the E-MOP/OMP. hmm , will have to see. but I have a feeling in about 50K miles. we will see the exact same thing.

TZ250

I think the author's point was simple. If you choose to run lightweight oil, use the best oil you can, and change it frequently. Sound advice from an expert.

nycgps

iTrader: (1)

I think another problem with this statement is that, in America, you dont always get what you paid for.

Group III oil could be called Synthetic is a good example.

I mean Group III is not bad. but hmm, not worth the Group IV/V 's price. and many people fell into that trap

madcows

+1

The crappier the oil grade, and/or the lower viscosity it is, the sooner it should be changed... Unfortunately, doing a complete oil change is a bit difficult - especially for those that are not in the know. Changing a little over half of oil system's capacity is not good, ESPECIALLY when mediocre oil is being used.

Time for me to figure out an ideal oil evacuation method.... Hmmmm... Perhaps some sort of modified oil filter and a fluid pump could get the job done.

ayrton012

Did I tell something wrong? No. I did not talk about that there are differences in thickness between a 30w synthetic and 30w mineral oil.
I told that a same weighted mineral oil is always thicker when cold vs. fully synthetic at cold startup.
------------------------------------------------------------------

Yes, every 30w is about the same thick at 100C, as every 40w...., and even a 0w is way too thick at cold start.

ayrton012

Otherwise I think it is very strange thing, that the S1 Renesis working with the same oil pressure like an average reciprorating engine.

I know that our oil system is shorter (less parts in the 2. section from the rear regulator..), but or E-SHAFT'S BEARINGS ARE WORKING MUCH HOTTER, than a crankshaft in a reciprorating engine. So we would need more flow-more pressure, mainly at high rpms, I think. It is only logical thinking, if I'm not closing to this technically.

9krpmrx8

iTrader: (46)

Can someone make a DIY on the regulator Mazmart sells?

dannobre

iTrader: (3)

Remove oil pan...unscrew regulator.......re-install regulator....replace oil pan

Oh you mean a real DIY ....

Sorry...My roof is leaking and I'm in a pissy mood

madcows

Some very experienced rotary guys around here are saying there IS enough oil flow so....

ASH8

More than likely if you use a higher oil viscosity of 15W40 or 20W50, which a few of the "experienced guys" are also recommending.

I tend to think it is the lighter weight Oils which are giving concern to Oil Pressure.
As the Mazda workshop manual says, "oil viscosity and Temperature can effect OP".

GeorgeH

iTrader: (2)

It's interesting that the Fuchs chemist reccomended a lighter oil for higher-revving engines.

And what is one of the major differences from our engine to older rotaries? Max engine speed, no?

nycgps

iTrader: (1)

rpm, the extra 500-1000 higher redline (FD vs FC)

but seriously, most people wouldnt spend more than 15 seconds at Redline once a week. so whats the problem here?

surreeee 5w20/30 is providing enough protection.

Use xw40 or xw50 oil. plain n simple.

some "so called" experts always wanna say something different.

Just like Global Warming, some "expert" say it does not exist, even with 1498703947124097 proofs out there north/south poles are melting, etc.

Some said 5w20/30 is enough, cuz this and that. you will lose hp with heavier oil yada yada ...

Enough protection? Im seeing opposite results.

Now S2 is out with almost double the pressure, just wait and see, have a feeling we're going to see the same thing (if its still 5w20)

Flashwing

Which "experienced" guys are you talking about? So far there has been two people I would consider experienced that have commented in this thread. One said lower viscosity oils are fine and the other is relaying what another expert said about the subject.

To be honest, the one frustrating aspect of this entire discussion is how quickly the information I've given has been dismissed. Even more so that it's been dismissed by some of the same people who have come to depend on Black Halo Racing for information and advice on matters such as these. Is there a reason that we're not trusted on one matter but trusted in another? Have any of you lost your engine to suggestions we've made? Of course not.

I see various RX8 owners taking the words delivered on high from some of these "experts" and seeing it as gospel. Where are these people? I don't see Racing Beat posting, I don't see Mazdatrix posting, I don't see Pettit Racing posting, I don't see any of these well established shops willing to come out here and contribute to these discussions.

The only exception to that has been Paul. I have a great respect for Mazmart. I'd like to see Rick Engman post up himself and state why using a 20w-50 viscosity in a RENESIS, or diesel oil for that matter, is a great idea. I've said before that BHR isn't satisfied with a "trust us" statement. If there's a reason, I know myself and thousands of other RX8 owners are interested in the technical aspects behind it.

What I REALLY want is for people to tell everyone why they made the oil decisions they made. I'd like to see those answers something other than "because I was told to".

I have my own theories as to why these suggestions have been made and it's got very little to do with technical aspects of the RX8. I'll hold them back until I'm certain it won't pollute the discussion.

So who are you going to trust with your RX8? Are you going to trust a company who is here every day giving advice and helping people get the most from their RX8 or "experts" that never interact with people?

9krpmrx8

iTrader: (46)

Yeah, I don't understand the people that spew out statements without explaining why they think that way or how they came to their conclusions. We all have opinions and for the most part they are useless.

We will see more results as more and more engines get torn apart by individuals and companies such as BHR, Mazmart, RR, etc.

Since I have been on these forums the consensus on engine failures has changed multiple times and honestly in my OPINION there is no one reason for engine failures. If the 09's last with 5W-20 then a lot of people will have to STFU.

madcows

If I'm not mistaking, there have only been two shops that have commented in this thread - BHR, and Mazmart. And both of these shops seem to agree that there is NOT an issue with factory oil pressure under typical use. There does seem to be a split, however, and that's concerning oil viscosity. I have come to my conclusion (both unfounded, and arbitrary): Low viscosity *might* be fine, but it should be high quality, and changed completely and often. I, however, will be sticking with higher viscosity oil which I feel will offer better protection under regular use - and not require the stringent effort required by low vis oil during changes.

This isn't a matter of trust. Neither mazda, nor any performance shop has come out with definitive proof supporting their recommendation. Since no one has proof, I will use my intuition regarding the matter which has stemmed from working on cars practically all my life. I might be wrong, but it's a chance I'm willing to take. Don't think I don't respect your opinion, but in the end, it's mine to decide. Thanks for your concern.

ASH8

Yes, 'ny' said what I was going to say...

Yes our engines Rev higher than ever before, but most owners don't use this high range very often or for very long..

IMO it is the age/use of the Oil which is the issue..even the Guy said, short distance and not reaching Max Oil Temps is an Oil grade Killer..fuel wash, etc.

And again...'ny' has said this many times before....
A higher Viscosity will protect for a longer period...

ASH8

I think it is also safe to say that Mazda increased the OP is S2 BECAUSE of 5W20 oils, as IMO 5W20 oil used in a Series 1 is not good enough for your OP, you need a 40 or 50 grade.
Particularly IF you do not change your OILS regularly...

You know we can go around in circles about Oil and Viscosity, Mazda have taken and re-designed a new Oil circuit never before used in a production rotary..until the Series II...why?...and it's not only because of the OIL Metering.

As we know the USA (NA) is the Only Country that says to use ONLY 5W20 Engine OIL..

Europe is a 5W30 as is Mazda Australia, BUT, the (my S2) Mazda Owners Manual says I can use any grade of oil depending on my Climate....for as long as I can remember it has always been that approach in Australia.

Sorry, I can't talk about a S1 Owners Manual in Australia as I have not cited one.