Castor 927 vs Idemitsu Premix
 

I've searched for premix oils and have found some great success stories of both using Maxima Castor 927 and Idemitsu Premix Oils. Does anyone have DOCUMENTED differences these oils made after tearing down two separate motors with one using Castor and one with Idemitsu? In addition, has anyone tried Maxima SuperM 2 cycle oil?

Sorry for yet another premix thread but I was tired of all the opinions and i wanted factual information or at least pics.

Good luck with that one...

Realistically, by the time someone would contribute time to drive two rebuilds thousands of miles with each oil brand and tear them down to show actual wear or carbon data is asking a bit much. Obviously you are just asking the question, and its fine. Just don't expect tons of informative responses. I personally use Idemitsu oil. I have a close friend that uses the cheapest premix at walmart.....

I think if you stick with a quality brand, you are good. Many people have used the OMP pumping grubby engine oil in there and making 3-400whp on the same engine for years.

Debating premix brands is like trying to find which "big brake kit" works best for my street car....

Idemitsu actually published detailed research on this topic years ago... unless something has changed, their premix uses a polybutene base stock. Their internal tests showed that this produces low carbon deposits in a rotary engine.

https://www.rx7club.com/attachment.p...1&d=1336777908

For the record, I won't hesitate to run Walmart oil + OMP in a rotary engine for most applications: not because it's good, but because people on the internet tell me not to, and I find this entertaining.

I'd stick with a tc-w3 2 cycle oil. Unless you're running e85, you need a castor oil. BTW I use castor927.

i read the study, and just to be simple, if deposits are lower with the polybuten base oil, and that is what Idemitsu sells, this is what you should use.

i'm sure you could find some other polybuten based oil, but the Idemitsu premix is available and not expensive....

I used castor927 on my other FD with no issues but then again I never had to tear down the motor and didn't have the car for long. My new FD has been using Idemitsu for years. I've been reading castor 927 is the way to go for E85. Would going from idemitsu to castor be harmful in anyway?

Idemitsu is the oil of choice both for premix and in the oil pan at IRP :icon_tup:

Another aspect in which I had delved is also what do these oils do to fuel related parts. Mainly to fuel injectors. Be interesting to see data on that. G

Idemitsu contains a special dispersant/detergent to help keep fuel injectors clean. That's straight from their website as well. They also have claims of helping with combustion sealing and what not. I personally run Idemitsu as I've been told it's pretty much the bee's tits. I've heard of many people also running Walmart 2 cycle. I guess it really comes down to preference and your own conscience. I feel better about myself knowing I'm pouring something designed for my engine into my gas tank. I premix as a failsafe to my OMP and its sensitive Oil injectors. I personally have not torn down my engine to inspect its internals or gone that deep into it. I can take pictures of it if it ends up poopin' the bed one day [knock on wood!].

Hope this helps
Matt

Agreed. Idemitsu is what I run as well. No metering pump. Premix 1 oz. per gallon.

If you ever run E85 not all premix oils will work. Idemitsu separates out in E85 and would be worse than running nothing. Maxima Castor 927 will blend with E85.

Since I don't run E85, I've been using the Idemitsu and like it. Less smoke than the Pettit stuff or Redline.

-Andy M.

i been using valvoline 2 cycle for my premix. im going to start giving the idemitsu premix stuff a try since i got nothin else to do with the FD.

its been running awesome with no issues and i finally have a chance to do other things than fix it :lol:

also running a 15psi methanol injected set up. now if only the website would work so i can place an order!

You don't buy from idemitsu. There are plenty of dealers around. I get mine from here...

http://www.dragonmotorsports.net/

I've bought over 8 cases from him. Maybe more.

Order mine from www.rx7.com

Great place but the oil is much cheaper from dragon. They haven't even updated the oil prices on rx7.com. The only problem with dragon motorsports is that they don't always have oil on hand.

thanks supernaut, got in touch with owner of dragon :)

ill be ordering a supply very soon.

anywhere else with good prices on Idemitsu, the guy at dragon isn't responding to my inquiry.

I was using Maxima Castor 927, loved it (especially the aroma, MmmMmm!) I switched to Blendzall Racing Castor (also smells good, lol) which was cheaper....turns out the Blendzall was a BAD idea, cuz now my apex seals are stuck solid w/castor gum/varnish... HELP!! -I'll prolly do what the lil r/c engine guys do... throw rotors in a crock pot/slow cooker w/distilled water + anti-freeze/coolant and "cook" 'em for about 8hrs...(not boil)...they say it gets their engines clean as new...