Is it okay to switch from a synthetic to a non synthetic oil? Or should i keep running synthetic?

Also is 0-w30 oil okay to use in temps where it will get above 80F?

 

It is not a problem to switch, however 0W30 is way too light unless you are living in sub zero temps.

A 15W50 or 20W50 or even a 10W30 would be a much better choice.

 

Okay right now I am running 10w30 Royal purple, Was thinking of switching to german castrol(0w30) or 20w50 syntec or GTX. Which do you think would be better, i know your the oil guru NA motor btw.

 

what temps are you starting in?

If it is above 30F consistently I would be using the 20W50 or stick with the 10W30.

I have seen a couple of the RX-8 13B motors ripped apart recently. The factory is recommending 5w20 in the USA and 5W30 everywhere else. It is kinda interesting to see the bearing wear is considerably higher with the low weight oil over the older 20W50 and 10W30 recommendations. Of the two reni US motors I have ripped apart, the bearing wear was what I would expect from 150K-175K instead of at 110K. I relate this to too light of a weight of oil being used (for emissions and mileage concerns).

Interesting the deposit build up on the Royal Purple ran long term MSP-RE rotary engines (not any more or less than conventional) is rather distinctive. Kinda like what your spark plugs look like at 10K if you have been running Royal Purple, but on the rotor face.

 

Thank you very much Icemark. Ill probably switch to the 20w50 GTX then. Thanks again sir.