On the RX8 renesis rotors, there is a ~3mm bevel on their sides, for good reason: half the time in a running engine, the ports are obstructed by part of the rotor as it sweeps past. In our FC engines, this edge is a sharp corner but in the renesis it is a more aerodynamic bevel shape. Looking for any last tweak I could do to make my s4 NA engine totally rock, I tried beveling the rotor sides like this the last time I had the motor apart.

Fast forward to right now. The motor fu$king rips harder than ever before! I didn't do anything to my ports other than minor little tweaks, and the engine definately has more port timing as well as a flatter power band up high. It could seriously not fall off above 7.5k rpm like it usually does, if only the rev limiter was gone (megasquirt 'n spark to the rescue). This is like having a bridgeport without the bad emissions and gas mileage, rough idle, etc. Oh yeah, the car is like a harder hit of cocaine now than it once was before, I just want to floor it up to 130 and back over and over again! The power band is unbelievable, it just wants more and more, the more you rev it the more it puts out.

Sorry I didn't take pics, but look at a renesis rotor and you'll see the full length bevels. Mazda engineers know what they're doing, and the renesis engine is a big improvement over our S4 NA engines thanks to this little detail, along with the higher compression ratio and super awesome intake manifold.

[/ramble]

 

thats amazing, i want to know how to do it, lol

 

Wow, that's frikkin' cool!

I mean, obviously the credit is due to the creators of the Reneisis motor, but dude, you deserve a cookie or something for doing it to your rotors and sharing it with us! lol

I'm definitely going to do this to my N/A when I get the rebuild/porting project on the road.

Thanks for the info LS.

Also, do you perhaps have a link to any Renesis rotor pics, just to see exactly what you were copying?

 

Great post! Add some emphasis to that.

I will have to get a renessis rotor when I have the S4 apart.

 

how bout them apples?!

 

There was a thread on this a while back.

I can't find it, but the conclusion was that it works, the "rotary gods" have been doing it for years, Mazda did it on the '8, and it adds big benefits.

-=Russ=-

 

Bingo. Now can you link to the thread with it?

-=Russ=-

 

will do hold on:
https://www.rx7club.com/rotary-car-performance-77/clr-motorsports-engine-running-412677/

 

Stock renesis rotor c/o mazdatrix.com:



Staticguitar, that's what I'm talking about! Wow!

KEEP IN MIND I did not balance the rotors after I did this, just eyeballed the bevel size and made them all uniform, and my bevels were slightly small compared to stock renesis. The motor does not vibrate more than it did before, not even at 7800 rpm when the rev cut hits, but I'll have to check for bearing wear down the road to know just what I can get away with as far as modifying a rotor shape without rebalancing it.

 

Also https://www.rx7club.com/rotary-car-performance-77/trimmed-rotor-431534/

-=Russ=-

 

Wow. There's a big difference between the CLR rotors & the '8 rotors.

-=Russ=-

 

Yah I think the CLR rotors are a little hardcore

Congrats Integra, glad to see you're back to loving rotaries

 

when i do a rebuild i'm looking into the CLR rotor phasing, b/c i dont think i could do nearly as good of a job as they could with all the balancing etc.

 

All it has to do is not break for a while and I'll stick with it, rotaries have some kind of addictive nature or something.

 

I know, I just dropped 891 dollars last night for stuff from mazdatrix for my build, still have to drive to atkins for the last few pieces and have them install my rotor bearings. Hmph, 9k+ rpms is expensive if you do it right heh.

 

The rotor champhering is the same as porting for timing (rather than volumn). You effectivly delay the close of the intake slightly longer.

 

didnt realize that icemark isnt too far away from where i live, weird

 

quit giving people ideas man.....



i can just see people in their garages now with a dremel grinding on their rotors to get more port timing out of them!

*sigh*

i hope you all realize if you do something like this the rotors need to be rebalanced or you will be losing some of the horsepower you gained from the imbalance and also be causing more stress on the stat gears and increasing the chances of a high revv engine catastrophe.

yes, i hate being the downer, but i had to say it. i would love to do a mod like this but i also know it needs to be done right to be efficient and last.

 

See my disclaimer on the last page..... also review my observations regarding engine vibration and perceived POWER of said engine.......

 

lol I hear you!

I am going to send mine to CLR I made up my minde on that one. I would advise the same to any inexsperianced rotary moder without proper equipment.

 

yeah which is why i said "i'm looking into the CLR rotor phasing, b/c i dont think i could do nearly as good of a job as they could with all the balancing etc."

 

Even if you send your rotors to CLR you'll need, or want, to send the entire rotating assembly off somewhere to get dynamically balanced to whatever RPM you're shooting for. After removing that much material from the rotors you'll need it.

I don't think what Integra did was major. Sure it's not adviseable for the newbie rotary porters/modders out there to go ahead and do this, but for him it's a fun experiment. He's been working on his ports for so long! They are hopefully finalized now, and pretty damn sweet!

 

i missed our second post, you didn't bevel them much at all im actually surprised you noticed much of a difference but i can see people trying to copy the CLR design and run into major problems, lol.

 

thats pretty amazing i didn't know they even made that "bevel" design


you learn somethin new everyday!

 

Yeah i pretty much shat my pants when i saw that rotor, CLR will have my money