SonicSVTF said:Uh... sorry Dave, but what old boy is thinking is right. You see, the Mazda RX-7 rotary engine actually BURNS OIL. Thats right, they actually have oil injectors that meter a minute quantity of oil into the combustion chamber while the engine is running. So they ALL USED OIL. Mazda recommended against using synthetic oil in these engines due to this characteristic.
And just to clear things up about the old RX-7's (of which I've owned many) Mazda sold them here through the 1995 model year.
...and they kinda did get "banned." The old rotary design couldn't meet the new U.S. Federal emissions laws imposed on the automobile industry for the 1996 model year. So Mazda said "well, these cars aren't selling anymore and we cant meet the new emission control laws, so we'll just not sell them in the U.S. anymore.
The completely new design in the RX-8 was squarely aimed at meeting the tougher emission standards and so now they're availale here again.
And one last note. Synthetics really don't lubricate any better than mineral oil under normal conditions. The only place synthetics are necessary is on a race engine that sees extremely hot oil temperatures... and possibly some cars with superchargers... or ANY car that has a turbocharger!
I have a supercharger and use mobile 1 5/20 synthetic. Change every 3000.
These cars do run warm, and I believe benifit from the synthetic. And I also don't care about the RX-7. I believed it was better not to burn oil. Makes the air smell better too but I do understand why the RX-7's had to.
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