A clean-burning, TCWIII two-cycle pre-mix or injector oil. Using Royal Purple 2 cycle TCWIII oil results in cleaner motors, more power, and better wear characteristics.

Racing Beat has been recommending the use of synthetic oils in rotary applications for several years. Our research has found that synthetic oils provide superior friction reducing between sliding surfaces, reduced foaming, and lower oil temperatures. We have tested several different synthetic oils and have found that while most offered improved wear and lower oil temperatures, none offered any horsepower gains... except for Royal Purple!


Right form racing beats web site. if anyone knows about rotaries. its them. Now someone clear this up;

 

Actually, Racing Beat have been using Amsoil synthetic in their rotaries since about 1973! If it was bad, you'd think they'd have worked it out by now!

 

They used to sell a different type of oil. I cant remember what it was.If you can find on of their old catollogs you will see that exact same paragraph in it with the other oil brand name instead of Royal Purple. They are trying to sell you something. Do you think they are going to tell you the Cons of using Synthetic?
You can use synthetic premix with no problem. You can also run synthetic with your OMP if you want. I don't think anyone actually knows the long term efects of synthetics in a rotary.
You have to realise that the engines they run in their race cars are torn down and rebuilt alot more than your typical street engine.
I am building a motor that will be producing around 400 RWHP. I will be running synthetic premix and Sythetic in the oil pan.

Mike

 

Thats right! It was Amsoil.

 

umm, ya, "2 cycle" pre mix or injecotor oil, I don't see anything about engine oil... totaly different!! 2 cycle burns clean, you don't want to burn syn. engine oil. and you can't but 2 cycle into your pan...

 

I go with what MAZDA recs. THEY should know.

TOdd

 

Yeah, isn't this a can of worms

You know, I've been on boths sides of the fence over the years. Swore by synthetic (Castrol Syntec) in my 82 (90-94) and use that in all my other vehicles. Presently run Castrol GTX in my T2.

Why, I dunno, scared by some of the other threads I guess regarding synthetics residues since we do burn some oil normally. Is that the right answer?? Don't know. But until I get my oil leak fixed, I'm using mineral based!

 

Me too. I tried Mobil 1 but it smoked so I changed to minera and it stopped. Then I changed to Amsoil and had no probs whatsoever. I'm running mineral at the moment but that's only because our weak-as-**** dollar means I can't afford Amsoil!
Figure this one out. Two of the most respected rotary tuners in the US are Racing Beat and Mazdatrix. One ran the synthetic in their 994hp Bonneville car, the other specifically warns not to use it. How the hell are us amateurs s'posed to work it out!

 

I have spoken with manufacturers in the Royal Purple company, and they say that they do not hurt a thing. Most other say to just use regular like Mazda says. Keep in mind that Mazda said that back when synthetic oil was not what it is today. I use it in both my 91 vert and my Project 86 track car. No problems with either.

 

LOL!! I don't know. Guess it's every person to their own opinion

 

if anyone knows about rotories it's mazda, and they recomend mineral

it's a simple fact that synthetic doesn't burn as clean as mineral and therefore leaving more deposits.
as said, the engines they're using are getting rebuilt every few thousand k's

 

Actually what you should've said is synthetic didn't burn as clean as mineral. Oil technology has advanced just as rapidly as other automotive technologies and the oil companies claim that their synthetics burn cleaner than they ever have, and as good as minerals. Whether you believe them is up to you!

 

Why would you want to run synthetic? Synthetic is good for high temps... but if your oil goes over 240 degrees your engine is cooked no matter what kid of oil you have, so what good is synthetic oil that can stand 300deg? Synthetic is also good for real low temps, but you're not supposed to get on your engine hard until it's warmed up anyway (possible housing damage if you don't wait), and rotaries have stone-simple oiling systems, no tiny hard to reach places. Synthetic doesn't break down easily... which means the crud stays in the engne, gunking up rotors and seal grooves. Synthetic costs a lot more, too.

So, what are the advanatges to synthetic?

 

In my opinion, if Racing Beat says its cool, then go with it. They know their stuff.

 

HOT: At 240º a synthetic is still protecting your engine, whereas a mineral is not, not very well anyway. Some parts of your engine, bits with oil in contact with them, are much hotter. Turbo bearings are an obvious example.
COLD: It's estimated 70% of the damage in an average engine is done in the first 60 seconds after start up. This is because the cold thick oil is in the sump, not in the engine. Synthetic oil retains the correct viscosity (stays runny!) over a much wider temperature range.
CLEAN BURNING: Much better than they used to be, maybe as good as mineral, but probably clean enough not to be a problem
COST: You don't get all of the above for free you know!

 

why doesnt someone go and fill up a glass with synth and a glass of dino juice and put a floating candle in each and let them burn out all the oil. then see if there is any residue in either. i dont know if this is very scientific or the results would be transferrable to internal combustion applications, but at least you could say that you have tested your ideas.

i'd do it but im lazy

 

Something else I just thought of. A good mate of mine who's a rotary mechanic said that almost none of the rotaries that came in dead died because of poor lubrication. 95% had a broken apex seal, nothing to do with lubrication. He couldn't justify the extra money for synthetic when it'll probably just break a damn seal anyway. BUT synthetics do a great job protecting turbos, which run at over 150,000rpm! So my advice is to run synthetic in your turbo, quality mineral in your N/A.

 

Very true. The combustion temp in a rotary is between 1200-1600F depending on a number of things. The flash point of synthetic Royal Purple oil is 400F. I would say that when you have something that burns at 400F, and you subject it to 1200F+ temps, it will burn.

I challenge anyone to show PROOF that any synthetic oil discussed here does not burn completely at 1200F.

 

At 240deg oil temp your rotary engine is OVERHEATING and will be damaged no matter what oil you run.

Watch your oil pressure gauge after you start your engine. Does it take 60 seconds for oil pressure to come up to normal? No it doesn't. Rotaries have only four bearings and a dead simple oiling system. Bearing wear is normally a non-issue, even rebuilders say they prefer to put the old bearings back in a rebuilt engine instead of new because the old ones are more reliable. What does that tell you?

I remember somebody tested synthetic oils, by physically burning them on a pan until there was nothing left, the synthetics left lots of hard, black, cruddy deposits. They do not burn cleanly! Would you take the chance?

As for cost... if you're that worried about your engine, use the regular stuff and change the oil once a month whether you've done 2500 miles or not.

 

i was wondering if there is a way to feed 2 cycle oil into the omp. i dont really know how it works so please explain if this will work.

Justin

 

you have shitty oil seals in your motor, why do you think it smoked with Mobil 1? cause the mobil 1 was able to penetrate even the slightest wear adn tear and seep into the chamber.

Mobil 5W-50 is the best oil for a rotary turbo according to RICE RACING

 

is that regular Mobil or Mobil 1???

 

peejay, pressure does not equal flow! At the same pressure, a cold fluid will flow less than a hot one. Engineering fact. Flow of oil is much more important than pressure. Anyway, read my earlier post, I don't think you need synthetic in a N/A rotary. Just turbos and pistons. You asked for the pros of synthetics, I was referring to engines in general, not just rotaries.
When was that test performed? I bet it wasn't recently.

HWO, (I know that's you Shane) the engine I was referring to was the 12A Turbo in my old 84 Cosmo. I put Mobil 1 in it when I bought it and it smoked, just a bit, mainly on start up. Next change I went to mineral. The next change I went to Amsoil 20W-50 synthetic. Modified it and spanked it for four years, always running Amsoil. No smoke. Oil seals fine.

 

Fully Syntehtic Mobil 1 5w-50

NZ Convertable - a lot of the guys on the skylines down under forum have experienced smoke when running Mobil 1 fully synthetic too and most people ya ask who have a clue on engine physics etc all say the same thing, its due to how much it penetrates.

in the end, the best soltuion for a rotary turbo is:

Ditch the OMP
Premix it
and run fully Synthetic oil in the sump

 

Hey, I used to run synthetic in my Subaru... worked great in that car, coolant temps went down a little, oil pressure no longer took 5 seconds to come up to normal on cold mornings, that old EA82 lifter rattle after extended idling went away, too bad it flowed so well it flowed out of every nook and cranny possible and went out all over the ground! I'd do it again on a boinger in a heartbeat, preferably one that was fairly fresh so the seals wouldn't all leak.

For a turbo engine.... MAN that is iffy. I understand the turbo longevity concern, and I suppose there are two ways to look at it... on the one hand, you can still safely use normal oil if you're careful to cool down the engine by idling it a bit before shutdown, but on the other hand if you're really pushing a rotary hard, any poor effects from the synthetic likely wouldn't come up in time for the seals to wear out enough to necessitate a rebuild anyway.