Hey guys, despite being a newbie and this being my first post I have done hours and hours of reading on the forum here about the RX8's huge Oil debates and what not so I can assure you i've done lots of searching. I know there is no right answer on what oil to use considering its more of a situational/climate conditions sort of thing. I just had a few questions regarging whether or not my oil + premix situation is okay. Heres a little info, I bought my Rx8 from from a very trustworthy rotary mechanic about a month ago so im coming up to my next oil change. The engine has 60,000KMS on it and I drive the car sometimes 15-40kms a day and maybe even 100kms on weekends. AND YES i do redline it a few times a day and do not drive like a grandmother. I live in Edmonton, Alberta, Canada which is cold in the winter but right now were coming up on summer and temperatures are anywhere between 20-30C and its fairly dry.
Anyways,
The synthetic vs mineral debate really is a bummer but i was wondering if its okay for me to use a non-synthetic 20w-50 in my location? That is what my rotary engine mechanic/builder/drifter reccomended. Ive also read though that you can switch to synthtic once your engine is broken in? (mine obviously at 60,000) also ive done some reading on the premix thread and came to the conclusion that it is okay to use premix (im getting idemitsu) in small ratios (600:1) if you do not have your OMP modified or whatever it is that premixers do (SOHN ADAPTER?). so if I fill up from near empty that would be 3-4oz at a fill up? Is all this okay? using premix with a heavy oil like 20w50? sorry for all the info but i felt it would be good for anyone willing to offer some information.
THANKS FOR READING THIS! CHEERS!

 

i use 10-30 in my engine and premix 8oz per fill up and i usually fill at around 1/4 tank

you will get 1000 different answers. im just telling you what i use. ive had my 8 for 5yrs

 

20w-50 is a pretty heavy oil.
our cars can run on pretty much any oil and I typically recommend something higher then the 5w-20 that is recommended for the US Models. Not sure what effect that cold weather would have on your oil choice, maybe a fellow Canadian can chime in.

As for switching to synthetic: You can always switch to synthetic and you can do it at any time. Some people will tell you not to, others will tell you that once you switch, you can never go back.
Honestly, it's up to you.
I have never used synthetic in my rotary simply because I figure it's not worth paying extra for an oil I'm going to change every 2,500 miles and it's more expensive to keep topping off since our vehicle is designed to burn oil as part of it's combustion.

As for pre-mix
You can either get a sohn adapter or you can pour the pre-mix directly into your gas tank.
Again, some prefer one method over another but it really is up to you which you prefer.
If it's worth anything at all: I simply pour 3-4 oz of Idemitsu in my gas tank every fill up.


To answer your last question: Is it okay to pre-mix with 20w-50: I don't see why not but then again, I'm not sure you need such a heavy oil.

 

Thanks for your help! Would you reccomend something a little lighter like a 10W-40 or 10W-30?

 

Go to Mazdatrix's website. You can get a decent deal on the premix they sell (idemitsu), either by the case or the quart.

 

...

 

ironically my story is the same with some boost added in for good measure

 

20w50 is to thick , id go 10w30 for the summer and 5w30 for the winter just my opinion. Idemitsu premix recommends half oz for every gallon (about 7 oz for a full tank).

 

0W-40 or 0W-50 is what you want.

 

who said 20w50 is too thick can be COMPLETELY ignored which is post #8, he has zero clue of what he is talking about..use 5w20 if you wanna kill your engine.

5w30 is ok if you never push your engine, but then carbon will kill it

so use what 9K recommends is good, actually, anything Xw40-Xw50, and try to use Ester based Synthetic.

As for premix, some people throw 4 stroke engine oil into the tank ... I would never do that as it clogs stuff up everywhere. basically any 2 stroke will work but you wanna something that won't kill cat (if u have no cat, use whatever), but I think I will go for something JASO rated. Or just use Idemitsu. Ratio can be from 1/2 oz per gallon if your OMP is working, more if you take OMP out (1 oz per gallon or more). 2 oz per gallon will get u a few more hp on Dyno. but for street u will again kill your engine(and your wallet)

 

5w-40 is the best weight for you IMO. It's thin enough for cold-starts during your cold-*** winters and thick enough for adequate protection when hot. Castrol GTX 10w-40 dino is what I use though. I don't want to spend the extra $ on synthetic since I change it every 2500 miles anyway. 10w-40 is good for year round use here, but the 10w might be too thick for your climate....5w is definitely more ideal. They just don't make a 5w-40 dino that's readily available (here anyway) :/

Oh and I use Quicksilver PWC Full Synthetic 2-cycle oil to premix. It's easily obtainable at Walmart (though I don't like them much, only place that has it) and it's JASO FD rated. I use 6-8 oz/tank

 

If thicker is better, how about grease?

Ken

 

I've used both 10w40 and 20w50 in all 4 of my rx's, never had a issue.

Due to your climate I would say 5w40 is right in your range.

 

On the topic, whats everyones thoughts on 15w40? I haven't decided what I will be using yet. I will be doing 4-6 oz Protek premix and was planning on a 15w-40 weight oil.

 

Do you drive the car in the winter? Did the Protek hot plate test convince you?

 

No winter just NY summer's 50-90F, and I got over a gallon of it for free so i'm using it lol

 

Free is good. If you don't drive in the winter it will be fine. What 15W-40 you looking at?

 

Haven't gotten that far, was recommended to use Rev O Max but I have never heard of it nor researched it yet.

 

I mean if you want a good 40W then just get a good 5W-40 or 0W-40, or even 0W-50. The 0W (Mobil1 and Eneos are good) oils typically are better from a formula stand point and will be good in any weather. But, if you change it often you will be safe with just about any brand name oil.

I used to use the Rotella T6 5W-40 with good results. You can see my oil reports on it in the UOA thread. But on this engine I have only used Mobil1 0W-40 and the test results are great so I see no reason to use anything. But if the price of the oil is a concern then the Rotella T6 is a great option.

 

Who does your testing? I don't know if I am entirely sold on a full synthetic yet. I was just poking my head in here just gauge some opinions I still have tons of my own research to do.

Oil debate aside, I have always used quaker oil, for no other reason than it was there and I liked it

 

I have used Blackstone labs for years. I have even sent them sample from blown engines without telling them just to see if the testing was legit and it is, the reports on the samples from the blown engines indicated problems with the engine. Synthetic is the only way to go.

Recently a buddy of mine (Houstonrx8er) had an engine failure and so we were both able to compare our failing engines (both well maintained, premixed, Mazda remans with about 30k on them when they failed) and the differences were pretty great when we compared different parts. My engine only saw Mobil1 0W-40 and he used Castrol GTX 5W-20 (or 5W-30 I think) and his bearing were down to the copper and mine looked awesome. I also had a lot less carbon build up, and generally thing just look great (except my failed coolant seal ), etc. It's obviously not a scientific comparison so it doesn't mean much to most but since we live in the same environment, both premixed with Idemitsu, our driving habits are similar (hard), and we both are OCD in our maintenance habits it was enough for him to now run Mobil1 in his current rebuilt engine.

 

Will research them tomorrow, appreciate the info. Now to go find those reading glasses

 

edited my post

 

I seem to be following a lot of your choices lately, opted out of an upgraded s1 starter yesterday and just went with an s2 instead. in my defense you are two far away to say that im trying to impersonate you, but my 8 is red

 

I have learned the hard way, smart move to learn from my mistakes.

The S2 starter is really an amazing upgrade. I got my new S2 starter in last weekend and when I pulled my buddies R3 starter off that I was borrowing, to put it back on his R3 we decided to put it another friends car who we already knew had low compression on the front rotor housing. Well he was having hard starts and could only crank about 208RPM's during the compression test. When we put the S2 starter on it, it cranked right up to 300RPM, even with low compression on the front housing.

It's an expensive option though.