can anyone explan this better in plain english?
 

I'm having some trouble explaining this on another website, it's a feature of the RENESIS, but people seem to think nothing has changed :

"
Counter-Rotating Fixed Gear And Tuning Of The Intake Sound: With the previous rotary engine, the direction of rotation of the fixed gear locating the rotors in the front and rear housing was the same for both rotors. With Renesis, the direction is reversed for front and rear rotors, achieving smoother rotation and reduced gear noise. Mazda also tuned the intake to give a satisfyingly sporty sound.
"

I take it that the fixed gears mounted to the housing have teeth cut in different directions, because the rotors themselves would certainly rotate the same way ...

hmm sounds plausible (the idea of teeth cut differently)...i wonder if rotarygod is awake:p

Virtually every technical marketing article on the web featuring the renesis carries the same paragraph, so I guess Mazda marketing put that information out there.

I just have a bunch of people on a different list who are rotary nuts, but yestertech engine models, who maintain nothing has changed in this area from the 13BREW and the RENESIS.

lol just b/c the look the same doesn't mean they are the same.

edit: not that i mind some things being the same teh 13b-rew was a beast:D but our engine is a very very very similar design..well other than the side ports..adn out apex seals being stronger (newer tech after all)..and outr side seals being stronger b/c they hav eto deal with the hot a$$ exhaust gasses. i believe our water pump is off the rx-7's (least it looked that way to me)...and the alternator. but i'm not really a rx-7 nut....:D btu you got to love them rotarys no matter what they are in.


ah yes ours doesn not fire in wasted spark mode (what ever that is called)..and i believe our firing of the spark plugs flip flops from idle to under load. hmmm well it's late and that's all that pops into my head. (ah yes rotars are lighter)...e-shaft looks like it's off a 13b-rew. and our ecu is crazy hella smart and has it's fingure in everything:D also our intake manifold is a lot better than the older ones.......hehe it also looks relly cool with all teh bends:D..i believe we also got 6 injectors as opposed to teh 13b-rew's 4 (granted they had bigger ones). i'm not sure if the older 13b's that were 6 port engines had 6 injectors...but it doesn't effect me so i'm ot to worried or into finding out:D hehe okay i am done ranting

I'll try....

The rotors rotate the same way, but because the front and rear housings face each other, the rear rotor orbits the rear housing in a clockwise direction and the front rotor rotates around the front housing in a counter-clockwise direction.

Image pulling the engine apart and laying the front and rear housings down next to each other on the floor. On one, the ports are on the right side, on the other they are on the left.

Thanks, the consensus on ausrotary is that the statement is plain wrong. There is no change in this area with the Renesis over the 13BREW engine, and it must be a marketing mistranslation.

So, does anyone know for sure?

Marketing gumpf... We all know it was Hymee that had to tune the exhaust to give it a satisfyingly sporting sound ;)

The cut of the stationary gears is slightly different to the RX-7, to reduce noise.
When I opened up an early production RENESIS about two and a half years ago you could see the difference, the RENESIS gears were ever so slightly rounder. It was very subtle, you had to really look to notice it.

Since then many people have said the gears are the same as the RX-7. I have not done the same comparison on any recently built engines, so it is possible the gear cut has been returned to the straighter RX-7 type, but when the RX-8 was released it definitely had different stationary gears.

And that statement you quoted, I don't believe that is from Mazda. Someone has cut and pasted bits of information so that it no longer makes any sense.

Hope this helps clear things up.