Alldaybored

iTrader: (2)

hi i was just surfing the web and i saw a few of those 10000rpm rotarys and i was wondering what it takes to make something like that? and if that 3000 more rpm helps? also ive heard of 13,000 rpm can it be done?

ultimatejay

iTrader: (1)

First thing you definetly need is a scattershield for safety. I shift at about 10k on stock unbalanced internals, but I am drag racing and am only at 10k for a split second. Pushing 10k plus on stock unbalanced rotating assy. for any length of time is flurting with disaster and the rotors may walk and hit the housings. If you are running a stock port or streetport then going that high defeats the purpose because it's out of the powerband. If you have a bridgeport or pport then going 10k + may be benefitial depending on port timing and set up.

To maintain these high rpms you should have high output oil pump- 100+psi, hardened stationary gears.clearanced race bearings. Balanced and clearanced rotating assy and rotors. And ideally a dry sump oil system. Hope this helps answer your question.

iceblue

ultimatejay good post. You need to close the port 3mm latter then stock to bring the power band to 10,000 so your not revving to the moon just to rev to the moon.

Balance and lighten the rotors please these things are so far off balance its stupid from factory. When we build boinger motors we balance our pistons within a half a gram our rotors are often 50grams apart!

Lebren

Pardon the ignorance and my noobness as this is my first post (long time member of rx8club)

The Renesis has a capacity of 10K or more, from what Ive heard it's capable of more but the trans cannot handle the revs. Can anyone chime me in on the difficulty of swapping one of these to the FD?

Alldaybored

iTrader: (2)

are 10 k rpm setup mostly NA setup or can they be done with a turbo setup also?

nillahcaz

iTrader: (2)

the easy way of looking at it is Air + fuel = HP
there are two basic ways to get more air fuel charge rev more or forced induction. there is no real point it pushing a turbo engine as high in the rpm band like an NA as more power can be made by upgrading the induction system. Can you have a 11k rpm turbo car. yes. Mazda back in the day *may still* sold NA PP and turbo PP housings where the intake was up higher in the housings to keep the intake exhaust overlap to an ok limit.
As far as EASY rpm the RX8 has a 9k redline and the older S2k's are 8.8k they did all the work for you. If you want something no one has do it right, If you want a turbo it would be better imo to use a 13bre if you would like NA hell try a PP intake side exhaust REN there is good info to show it works but never seen one in a car. but just like the piston world the higher you move your redline with out major engineering, the harder the car is to DD.

jantore

There are a few things u need for a 10k+ rpm engine.

1. All new engine parts with the right porting, either Bridge Port og PP port
2. 2 Piece 13b shaft
3. Lightend rotors to excact same weight
4. Ceramic 2mm 2 piece apex seals and corner seals
5. Lightend flywheel
6. Balanced assembly
7. Dry sump oil system
8. A well built exhaust system, that can handle the extra rpms
9. Injection controlled engine with a good ecu and CDI coils
10. A realy good engine builder and tuner

Ive probably missed a few things. But this is basicly most of the things u need. A good engine builder that has built rallycross engines will be able to build it. But remember one thing, the milage drops alot for evere 1000 rpm above 9000 rpm. U could probably get 30 000 miles out of a 9000 rpm engine, and maybe 10 000 miles out of a 10 000 rpm engine. And then maybe 2000 miles out of a 11000 rpm engine. And then maybe 800 miles out of a 12000 rpm engine. And then a rebuild after ever race weekend of everything over 13000 rpm.

JT

nillahcaz

iTrader: (2)

Funny my old 10k had less than half that and ran 25k miles till the radiator hose popped.
Used RE housings simi jport s5 internals that where clearanced and balanced. running a carb and dizzy with LS1 coils for non wasted spark conversion and a blaster 2 with duralast cap and rotor. window bearings wet sump and stock flywheel we had mag particle tested. carbon apex with treated springs. and webber jets in the e-shaft.
The apex springs are more important than what the seals are made of in an NA as long as its not the stock cast ones. hop is what will kill it fast.
running a basic RB exhaust with the addition of a xpipe.
saying a 9k engine will only run 30k miles, Mazda must have a lot of warranty work on the RX8's and the Suzuki RE5 would be lucky to make it off the sales lot.

nillahcaz

iTrader: (2)

Im to late to edit. The suzuki was not the one i was thinking of it's the Norton bike line that have high rev wankel.

jantore

Well this is with extreme tuning like a big BP and PP ports. A streetported engine will probably last longer. A freind has a 12a that has gone about 250 000 km and have been abused at the track for the last 6 summers. And gone up to 10 000 rpm every singel time. So it can go further. But the milage on the engine drops alot due to the wear of the side seals and corner seals at high rpm.

JT

ultimatejay

iTrader: (1)

^These are good things, but I think you are being single minded. You don't need fuel injection, a Carbuerator system would work just fine too. You dont' need ceramic apex seals- carbon apex seals will work just fine and I know of others using different seals with great results too. Although a 2 piece e shaft would be nice, it's not neccessary on an all motor car and a stock unit will be just fine. My friend uses the stock unit and he goes over 12k with no problems. I think one of the main things to have for longevity is a really good oiling system like you and I mentioned and of course balanced/clearanced assy. Alll the other points are just added benefits.

Other than a J port, I don't see how porting variances can cause an engine to last longer. If they are both going over 10k, then the wear and tear on the internals will be the same regardless of porting. On a J port the silicone coolant seal will only last so long before it starts to leak. And I think a 12a will last longer because the engine is shorter and the e shaft does not flex as much.

Lebren

These are good things to know! Ultimtejay, do you think the 16X will resolve a lot of the issues that we are having with the REN?

PvillKnight7

iTrader: (16)

how do you balance rotors?

FelixIsGod29X

iTrader: (50)

Not sure if its been said yet by cryo treating the stat gears would be handy and also race bearings for more oil lubrication. Plus higher oil pressure.

diabolical1

iTrader: (3)

the simplest answer i'll give until you research the details is:

take this and run with it ...
all i'll add for now is of course you'll need to provide air to the engine as well.

Alldaybored

iTrader: (2)

hmmm I wonder if you can make like 250 hp with something like this? what would happen if you tryed to run nos in one of these motors??? for more air could you try a meth setup????

just trying to bounce some ideas off you guys what do you think?

ultimatejay

iTrader: (1)

How about 400+hp.

slpin

iTrader: (9)

dude...
the rotor is spinning at 3k when the tach shows 9k rpm... the rotor bearings are seeing 6k...
it doesnt see the force of sudden acceleration and sudden deceleration and direction change like in a piston motor...

it is not really that big of a deal if you make power up there

and it is not like you are going to care about longetivity at that type of rpm... surely it is not a daily driver...

i mean... .you probably want a new regulator for oil and differnt bearing clearancing.... 10psi per 1k rpm is the norm...

the things that you probably have to worry about are the things around it... like having a clutch explode and cut thru the floorboards....

Alldaybored

iTrader: (2)

what about 3 rotor motors or 4 rotors can they run at these speeds or do they not like to rev this high. really 400+ hp ... thats pretty cool hmm it makes me want to build a race car. is that a PP setup??? 400hp would make a great track car, also i wonder how long the tranny would hold out and the rest of the drivetrain trying to do this.

so do you think a 3 rotor can get close to 500 hp na? or is that to much to wish for?

nillahcaz

iTrader: (2)

the r26b as well as the older 13J-MM mazda 4 rotors had a redline of 9k and 700 / 630 NA Hp respectively, you can spin them faster but the gain will not be as big as with a two rotor. Drag on the bearings, seals and gears play a part in this, as well as balance. The longer the e-shaft the weaker it is as well....

Alldaybored

iTrader: (2)

wow 700 hp isnt that in a PP set up? i wonder how much torque it makes? thanks guys for help with theses questions just trying to learn some things

Alldaybored

iTrader: (2)

Im not so sure i understand this??? so what your saying is nothing spins any faster it just gets more power when you add more fuel and air? kinda like a rotor on a chopper the blades just tilt and push more air??? (that was a 2 year old way to try and say it) am i right with this?

jgrewe

iTrader: (1)

The more air you can get through an engine the more power it can make. So if you need to spin it faster to use the dispacement of the engine more times per second that is fine.

BUT, there is no use spinning an engine that high if you aren't going to be able to feed it more air, ie. Porting.

The engine can handle 10K with very little work. There are a bunch of other things to worry about when you start spinning things that high. There is a video I remember on youtube of an RX4 IIRC that had a flywheel/clutch let go on the strip. It hit the ground, and bounced back up cutting through the cowl of the car and disappears out of the picture in the sky. It would cut your feet off if it decided to jump that way.

Alldaybored

iTrader: (2)

Ok i know what your talking about and I understand at those speeds your drivetrain is having to work like 3 times harder then i should . as for the air thing could you run nos to get more power? is it even smart to try it??? how well does a rotary work with nos or is a bad on the seals???.

nillahcaz

iTrader: (2)

N2O info for rx7's
NOS is a name brand and it bugs the **** out of me when some one refers to nitrous system that way.