Geek stimuli can never be overrated. I read threads with any kind of data whether I consider it useful or not.

No, it's not. It's about the oil, plain and simple. Issues with oil delivery (or lack there of) will be there whether someone uses the right oil or not. Regardless, the discussion in this thread is about oil that'll maintain its lubricating properties the best in this engine in the posted environments. Compiling a "database", as unscientific as it may be, definitely doesn't hurt to compare exactly how different types and brands of oil are behaving.

eric--glad you came in
several "things" have already been discovered for street driven cars.
1--oil viscosity is NOT holding with the 20-30 wgt oils and with some 40 w oils. They are searing down to one step below (40 to 30,, 30--20 etc) in as little as 1K miles. csct's are below 3.6 for some oils.
2- fuel dilution--can be a problem with short drives and idling warm ups--short drives in my case is 12 miles!! It is very important to get the oil temps up as with cooler ambient temps a lot of people are never seeing oil temps over 160F (open road driving).my last one on a 2K change fuel dilution wa 1.8%--not real high but high enough to affect my viscosity and i am runnig deisel oil!
3- there is abnormal front stationary gear bearing wear in a LOT of engines. Seemingly visocosity related. It is advised to run no lower than a 40W oil--but then again some 40 wgt oils sear fast. So uoa can identify which are holding up and which arent.
olddragger

Yes and I should add that the viscosity numbers were low with the GC 0W-30 I was running and that was only after 1500 miles. After 3,000 miles it would have been much worse.

1. Is it normal for viscosity breakdown in non-rotary engines/are we thinking that this is a problem? Perhaps all oils do this? Just like all milk will ultimately spoil.
2. Don't understand
3. Is this wear the root cause of engine failure? In otherwords is this the one thing that if fixed will make your engine last longer?

I understand the purpose of the thread and I sincerely hope I'm not changing the subject (which I probably am) however something tells (I'm probably wrong) that all this data collection is being done so that people can choose a more optimum oil and therefore make there engines last longer prior to thier demise/need for additional service.

Merry X everyone

I think most engines currently fail now due to low compression - too much heat, too much friction, too much carbon. There are plenty of people blowing up engines in other ways but I guess that could be described as the difference between the motor failing and the user breaking the motor. However, as engines are getting up there in miles people who have had good luck with their premixing, heat, and carbon might start seeing new modes of failure. Engine autopsies seem to indicate that while part A gave first, part B may not have been far behind.

Personally I am on my third Renny despite meticulous oil change intervals and maintenance so I am looking for every little piece of info that may help me to increase the longevity of this engine.

Eric
fuel dilution= blow by and yes some cars are getting enough of this that there is a need to keep an eye on it if you want a 100K engine. I think its mostly driving style and low oil tempt that may be adding to this. Idling until the oil/coolant is "warm" may not be something that you need to do. car runs very rich at cold start idle. Maybe idle just for a few seconds then drive at no higher than 3K rpm with a very little load may be a better way of warming?
bad injectors and poor "crancase" ventilation. can also cause this as you probably know.
2- the rotary seems to sear oil faster than recips--reasons i really dont know--maybe wide babitts and close tolerances?
3- the front stationary gear bearing is going through the copper in as little as 50K. MY THERORY is that if the e shaft has a "wobble" anywhere then that will affect everything.Even rotor stressors/movement. Just my theory, but I KNOW on recips if a main bearing allows wobble then you have big trouble.
enjoy your input as always----Travis did a good picture of you---you aint that good looking!
OD

The RX8Club has become quite the family and or group of friends. It's all about communication and there are many things that people enjoy chatting about. Our cars provide a focal point of common interest.

Oil related issues are not the main cause of engine failures but oil related problems have been identified in a great number of engines. Viscosity breaks down in every type of engine but rotaries do have their own peculiaralities. These types of tests provide information that is useless to some and helpful to others. Just as you pointed out, we can look for signs of deterioration like copper content and other such things.

Paul.

Merry Christmas Paul!
Got the 09 tranny in but it was late before i finished--pilot bearing was shot due too my main shaft play and it put us behind---way behind. So i didnt get to come by. I think i was hallucinating on the way home:) at 2am.

I will forward my 1st uoa to you later. Glad I did it--believe my driving style needs to change and i need to get my oil temps higher than they are. Nothing really abnormal--like wear associated with new engine breakin- but my viscosity even with the.deisel oil was lower than it should have been.
OD
OD

I'm getting oil analysis done to verify my oil is doing it's job of keeping the metal bits from rubbing each other the wrong way. I am tracking the snot out of this car (and hoon it around on the street too), so I want to be aware of unusual wear as early as possible. If the bad metals take a big jump in a report, I'll know that I've overdone it and it's time to get another engine built before catastrophic failure. I'm not getting it done to choose the optimum oil (oil is oil) beyond maybe adjusting the viscosity I use.

And yes, there is some data geek in me that loves spreadsheets...

i sure have learned something---get the oil temps up during everyday driving and dont warm up by idle.
OD

I've been saying that for years; get in and drive :).

Paul.

Stationary gearset loves to shear oils simply from the pressure, hence me recommending the 50w users perhaps try the specialist Millers oil designed for the Mini, as that also shared it's engine oil with the gearbox, under similar conditions, and has a great EP package as a result.
I'll have a word with the rep. when he comes around and see if it's possible for them to tweak a lower viscosity version for us.

i have now blocked both oil coolers (mornings in ga in the 30'sF and warms to the 50's during the day) in efforts to get my oil temps up to 180-200 during my 10-12 mile commute to work.
It helped. It was 36F this morning, warm up was quick-and I got to 180 on the interstate and 185 once in the city. Coolant was 170F or so.
At this point I dont know what else to do--maybe wrap the coolers? Not just block them?
OD

I am going to try and block mine and see what a diff it makes. It's been in the 30's here in the morning too. I noticed some froth on my dipstick when I checked the oil on my road trip and the engine and oil was still hot.

The problem with that logic is the heavier viscosity oils shear much much faster when running at high RPMs and high load.

Edit:

The UOA collection for the Eneos 75w-90 is available here as well.

I'm not recommending a 50w, I'm recommending that those that do use a 50w, try the millers and report back ;)

Personally, I'm sticking with 30w myself.

i think most of us that use 50w is for track only then it is changed out for a 40W?
Doesnt the brand of oil also make a difference in shearing--diesel does not shear as readily as regular engine oil for example?
od

Touche' Phill! I realize I'm being pretty stereotypical with some of my information but I simply don't have the luxary of testing out all these oils. I'm seriously insane about this stuff enough that if I could I certainly would. Posting these UOA's is a great idea and I hope more people post up whatever oils they use whether the experience is postive or negative.

The brand is iffy but certainly the base stock is going to make a difference. Since synthetics use much less VI's you're going to seriously reduce shearing. VI's are the largest molecules so they are the first to go.

Without getting to much into the science since it's off topic I'm starting to actually think that people should be using a thinner (GASP!) oil on the track then they should be on the street. The only major deal breaker would be the oil temperature. Assuming your oil temps are not out of control on the track, the theory holds true. Even still, a thinner oil will flow easier and shed heat better.

Look up information on the hydrodynamic wedge. The short of it is higher RPM's and or bearing speed actually increases your film thickness instead of thinning it like typical judgement would dictate. The Stribeck curve confirms this. As RPM's increase you move from a boundry layer or mixed lubrication into the hydrodynamic region. Since track conditions involve mostly high RPM's it would explain why race motors don't have the same bearing problems that street cars do.

Running a thicker oil on the track won't do any harm but it will greatly increase fluid drag which, in races like the koni challenge, mean losing a few precious horsepower that people with RX8's need.

I'm assuming you do not have an oil thermostat in your system? We have found these to be critical to get to a good operating range. Too big of an oil cooler size/solution (we refer to ours as Pizza boxes) are so effective you get too much cooling---130F max on a late fall/winter/early spring track day. An oil thermo is not as restrictive as we thought (doesn't make the engine run too hot. Our big oil cooler w/oil thermo runs about 185 F all the time. Hot or cold. Something to think about. The "tape" thing can be a "put more on, take some off, put more, take some off" effort.

only have the oem one--which i seriously question. I am beginning to think that an aftermarket may be an option to my mentopausal engine.
Right now with both coolers blocked (front side only) I do get well into the 180's most of the time.
I am getting less milky stuff now and have decided to do 2K mile oil change with a filter change every other time. Still using deisel. I will do uoa on every change for the time being.
I can actually get a tad over 4.5 quarts out by parking on a hill and using an evacuator.
Or use ramps and evac.
OD

OD have you seen the RB oil line kit? I wonder if it will help with pressure and flow while retaining the factory thermos (if you can call them that).

http://www.racingbeat.com/FRmazda4.htm

Funny they say replacing these should be done when the engine is out, it's really not that big of a deal to do with pre made lines. The hardest part for me was cutting, fitting, and adjusting the lines since everything was custom.

Oh, and the price for that kits is ridiculous. You could make those using the best hose and fittings for $200.00 or less.

saw them and at present not interested for that price!
Flash--understand what you are saying and i am certainly seeing the value of used oil analysis.
One of the reasons i like the diesel oil is the higher resistance to shearing. i have been told by someone that works in that business that diesel oils are really as good as some so called synthetics.
I dont know all the tech--i read== but what info do you believe--right?
Running the lightest viscosity oil that meets your engine needs is the best way to go--no doubt. That also goes for the trans and diff:)
Trick is -----finding that right viscosity/oil.
I will be changing oil q 2 K now until i can get a better look as to what is going on.
OD

Yeah they are crazy expensive but there may be better solutions soon.

Finally got my 0w-20 UOA back! I also had a TBN performed to see how long this oil could be ran. It certainly looks like a 4,000 mile oil but because my sample method was piss poor I'm questioning some of the results.

My comments for this report and all my other blogs are here.

http://flashwing.blackhaloracing.com...kstone0w20.JPG

wow dude--maybe some thinking to do? are you running a k&n filter?
oil holding up ok but i rather have more phos and zinc in it?
OD

No I am running an AEM dryflow air filter with the sock attached to it. Although it's been some time since I checked the clamps to make sure it wasn't loose. I am willing to bet the sample picked up some particles on the oil pan itself.

I was honestly expecting this sample to be crap so it's anyone's guess. I'll check it out to be on the safe side but hopefully the next sample will show much different results.

so your filter is outside the engine bay--right?
AEM should be ok-shouldnt it?
Hate to see that bro--those puzzles can be a real challenge.
i hear that shop vac filters wrapped around the cone filter helps-- i have one on mine!
OD

The filters are good for 20,000 miles but it's possible I might need to order another one. Still, a blocked filter element and one letting dirt through is totally different. It will just require me to remove the bumper and check everything out. It might give me an excuse to do some other work I need to take care of.

I'm not too concerned. This motor has about 30,000 more miles left before it gets rebuilt anyway.

What is Molybdenum? It's like 400 higher than it was in my UOA. They said my silicon was high but yours was twice as high as mine. Weird.

Also taking the sample from the oil pan as its draining is okay according to Blackstone. You said you dripped it from the pan bolt?

Also, just my thoughts but you said when you switched oils you may have left a quart or two of RP in even though you drained the coolers and I highly doubt that because when I removed my stock coolers there was only a little under a quart of oil between the two of them and all the lines. There is not as much oil still in the system as people claim there is. When I drained the oil to install the single cooler the car was on jack stands as usual. I thought there woudl be much more oil in the lines, etc. But the fact is that there just wasn't because we actually used a empty quart of Mobil1 so we would have a good measure of just how much was in the coolers and lines.

You normally see it as molybdenum di-sulphide in CN grease, it's a high pressure lubricant, the sulphur providing the cushioning properties as it does in titanium di-oxide, which is starting to creep in more now the price for it is getting closer to moly.
However, seeing as there's no suphur in that breakdown, it's possibly in the form of molybdenum phosphate, which helps with wear, especially at startup as it can be made to cling ionically, and provides good corrosion protection, or molybdenum-enhanced urethane, which is the more normal form, but unless I'm reading it wrong there's not enough of the rest of the required elements for it all to be contained as such.

yea moly is not bad stuff--just different oils have different additive packages. Diesel oil for example has very little moly but a LOT more zinc and phos.
OD

Ah hah, good to know. Can't wait to get my UOA to see how my Mobil1 0W-40 held up.

Zinc and phosphorous are the two that the EPA have attacked as being catalyst killers. We know that they are wear inhibitors.

Paul.

How important is zinc to the Renesis as opposed to regular engines? How important is it to regular engines? I have only heard it referenced in issues with specialized valve trains.

I noticed that in the Eneos oils that the lower weights are ILSAC GF4, but that the 0W50 is not. That is one of the reasons i had stayed with Mobil1 0W40 in my last car because they hadn't taken out the zinc.

Is it in yet? I've been running diesel, but I'm wary of it now that I know that it's high in zinc and phosphorous since I don't run a SOHN. The Euro Mobil1 would be my next choice since it covers cold starts and would hold the 40 viscosity better from shearing since it's full syn and starts with a 40 weight base. Has anyone used this oil long term on a Renesis? I remember reading in a couple of other threads that Mobil1 specifically was a syn oil that was to be avoided with rotaries, but I think that was the North American faux-syn oil.

Rotary Oil
 

As a 57 year old Exxon Oil distributor, IMO that any major Sm spec oil or any oil made since 1970 will get maximum miles outta your renesis. Yeah, I've done Blackstone lab analysis, but it's mostly to tell you if you have excess dirt, antifreeze leak, or excess fuel.
My favorite oil is Mobil 1 0w40 changed at 5,000 miles, but, diesel oil 5w40 TDT of Mobil, Shell, Chevron, or Exxon is probably good also. Flat tappet cam engines or other cams are way harder to lubricate.

I had a 1973 Rx3 that I kept balls to the wall on 110 mph cruises with Exxon Uniflo 10w40. After a few years and 75,000 miles the water seals on the housings started seeping so I'd have to take out the plugs and heat in the oven to restart. Never was stranded. I bet it could've driven for months, all over U.S. as long as engine never cooled overnight. Imagine how you can over heat side housings without cool down stroke of 4 stroke.

The second engine went half those miles because I lowered my rear gears 10% and was driving 7000 rpm (that models redline) for 30 minutes in 100+ degree weather, and one apex seal blew with instant blub blub like hot cam. I even restarted it to drive to get used Rx4 engine. Those engines had oil flow into the carburetor with what seemed like 1,000 mile quart use for me, but in hindsight I think I would put in a few oz 2 stroke motorcycle oil in each 12 gallon fill.

I have not got my UOA yet but it should not be long now. Check out this spreadsheet of my MPG that I have been keeping track of since November. Notice how the MPG varies so much. There are a couple of highway road trips in there where you see the MPG bump up and teh space with no data is because i lost the damn receipt.
http://c1.ac-images.myspacecdn.com/i...cd3131ec38.jpg

I pay Double that for GAS/Petrol...took $80.00 AU on Tuesday for 58 Litres...or $74.00 US Dollars!!!...

We in Australia are being RIPPED OFF by the Oil Companies...

We in Australia are being RIPPED OFF by the New Car Companies...

We in Australia we are MUGS (Fools, Dopes) for Putting up with it...

Holy crap!!! That's expensive. Keep in mind that all of these fill-ups are on Shell 93 octane, I do not fill-up with anything else.

If you notice, I actually found it for $2.53 a gallon, that was a treat.

Aw dear, it must be terrible, try it at $1.80 per liter...especially when it does 0.35l/km

Holy Shite, and I was crying a couple of summers ago when it was like $55-60 to fill-up my ride.

A 58 ltr. tankfill in the Netherlands costs USD 120,-
1 Ltr. Shell 5w30 synthetic oil costs approx USD 28,50............
At last but not at least...............latest price early 2009 of the 231hp Renesis was USD 81.500.-...........due to horrible "luxury"- and CO2 taxes...........
Only 350 RX 8's are running in the Netherlands (18.5 million inhabitants)............
Mazada-Netherlands skipped the new RX 8 in the course of 2009 from their salesprogramme since it is unaffordable with those taxes........

Best regards, Ruud

Yes, but your distance to travel is very small compared to USA or Australia.

Isn't it funny how oil companies "scale" their Oil Prices...

Generally, small countries, higher prices, large countries (land mass) lower prices..

Isnt most of the difference usually because of taxes?

That depends how far you drive each day, I used to do 4 hours of commuting per day, 5-6 if the traffic was bad...

ever heard of technology suppression? The present day guys will maximize profit on what they have before they will allow new tecnology to be produced. We have not gotten to that point yet with oil. Probably wont in my lifetime. But my grandchildren will be driving something totally different.
OD

Sorry, I couldn't resist :)

http://pix.motivatedphotos.com/2009/...paragraphs.jpg

synthetic motor oil
 

Moly additives are for extreme metal sliding and vibration that might be encountered in machinery and in car camshafts. Zinc and phosphorus react under heat as first line of anti-wear defense for sliding parts like camshafts, and moly would be second line of defense. We sold moly grease for pivot points, but if you used for bearing repack it could plate out on bearing runs like mud and run tight. Also, the sulfer in moly disulphide grease would eat rubber ball joint seals. I believe the moly compound in motor oil is different without the sulfer, so its ok if deposit control has been tested by refinery, but not necessary with RX8's nice big bearings.

Diesel engine oil has the better additives for soot control so they are usuallly best for any combustion engine.

The #1 reason for rotary failure is apex seal wear, carbon accumulation, and holding steady high rpm like 8,000 for a few minutes. My 2007 RX8 only uses 1/2 quart in 2000 miles, so I premix approx 4oz per fillup with Mobil 2t motorcycle oil which I stocked up on because they discontinued. That makes about 2/3's of seal lubricant my premix and 1/3 the Mobil 1 syn 0w40.

Two stroke motorcycles can have real bad exhaust port clogging so refiners have done lots of testing on oils that burn clean. I'm thinking thats what I want to lubricate and sweep out burned oil ash in my rotary. I think Castrol has 2t also.