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What is Max RPM before failure

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Old Mar 27, 2009 | 03:48 PM
  #26  
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Originally Posted by kersh4w
why do rotaries fail? carbon buildup.

you think carbon buildup is a problem doing 9k rpm @ WOT?
Yeah, I think the only issue you could see then is overheating from poor cooling or bad oil/oil circulation
Old Mar 27, 2009 | 04:48 PM
  #27  
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Am I the only one that shed a tear watching that video? That was just wrong ... Back on subject though, if you want high revving, get a motorcycle 15k redline

Last edited by J wind; Mar 27, 2009 at 04:52 PM.
Old Mar 28, 2009 | 01:26 AM
  #28  
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wow, didnt expect that many responses, this question stemmed from losing my job to "streamlining" and finding a higher paying one with more disposable income.

I was comparing it to my brothers $3000 built b16 (which is cheap for building a motor) used in autocross just because i love the response and sound. i am a formula one fan (watching it as i type) so high revs are what i like, hence buying the 8.

I also asked what would be needed to be able to perform this and from the answers I have read, a much stronger apex seal is needed along with side seals. and also gears. oil metering isnt really an issue if you add in 2 more to kick in past 8500. and probably lightweight rotors.

I know of several manufaturers of flywheels that are capable of high revs and there are a couple clutches as well.

so from what i can gather im looking at about $10000 to get this thing to 12k rpm?
which I think this is going to make me lean toward an s2000 since I know how to get a honda up there already.

oh and just to clarify I do know that there are ancillary and supportive systems upgrades needed as well, i was just wondering the needed mechanical hardware
Old Mar 28, 2009 | 01:33 AM
  #29  
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Old Mar 28, 2009 | 01:57 AM
  #30  
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Originally Posted by notorque
wow, didnt expect that many responses, this question stemmed from losing my job to "streamlining" and finding a higher paying one with more disposable income.

I was comparing it to my brothers $3000 built b16 (which is cheap for building a motor) used in autocross just because i love the response and sound. i am a formula one fan (watching it as i type) so high revs are what i like, hence buying the 8.

I also asked what would be needed to be able to perform this and from the answers I have read, a much stronger apex seal is needed along with side seals. and also gears. oil metering isnt really an issue if you add in 2 more to kick in past 8500. and probably lightweight rotors.

I know of several manufaturers of flywheels that are capable of high revs and there are a couple clutches as well.

so from what i can gather im looking at about $10000 to get this thing to 12k rpm?
which I think this is going to make me lean toward an s2000 since I know how to get a honda up there already.

oh and just to clarify I do know that there are ancillary and supportive systems upgrades needed as well, i was just wondering the needed mechanical hardware
this is the serious answer.

call mazmart. talk to paul. tell him what you want. then, ask for the guy in the back room..

he is sharp..

apples and oranges.

simple.

beers
Old Mar 28, 2009 | 02:02 AM
  #31  
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Damn, I wish the s5 in that video shouldve blown up. Look at that fire underneath the car
Old Mar 28, 2009 | 10:00 AM
  #32  
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Originally Posted by notorque
wow, didnt expect that many responses, this question stemmed from losing my job to "streamlining" and finding a higher paying one with more disposable income.

I was comparing it to my brothers $3000 built b16 (which is cheap for building a motor) used in autocross just because i love the response and sound. i am a formula one fan (watching it as i type) so high revs are what i like, hence buying the 8.

I also asked what would be needed to be able to perform this and from the answers I have read, a much stronger apex seal is needed along with side seals. and also gears. oil metering isnt really an issue if you add in 2 more to kick in past 8500. and probably lightweight rotors.

I know of several manufaturers of flywheels that are capable of high revs and there are a couple clutches as well.

so from what i can gather im looking at about $10000 to get this thing to 12k rpm?
which I think this is going to make me lean toward an s2000 since I know how to get a honda up there already.

oh and just to clarify I do know that there are ancillary and supportive systems upgrades needed as well, i was just wondering the needed mechanical hardware

I think it's going to cost a whole lot more than $10,000 to do that. What are you going to do about the transmission? And what are you going to do to produce power at 12k RPMs?

Are you really willing to spend that much money and likely burn up your car all for the sound? Why not just go turbo and get an aftermarket exhaust? That would be a good way to spend that money, IMHO.
Old Mar 28, 2009 | 10:20 AM
  #33  
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High RPM doesn't create power. You could rig up a Buick to rev to 15,000 RPM. Doesn't mean anything. It'll just stay in gear longer and lose more and more power as it drops further away from its VE. Its the ability to flow sufficient air at those RPM that creates power.
Old Mar 28, 2009 | 12:27 PM
  #34  
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Originally Posted by swoope
this is the serious answer.

call mazmart. talk to paul. tell him what you want. then, ask for the guy in the back room..

he is sharp..

apples and oranges.

simple.

beers
thank you, I appreciate the answer will do.



and yes, if worked out "properly" higher RPMs will grant more power, or a broader power band, and at the least more time in a lower gear to do more work.

and there are videos all over of cars both with same peak power, one turbo and 8000rpm redline, and an all motor with 12000rpm redline, and the higher end all motor will always beat them, not to mention the throttle response you get from NA cant be beat by forced induction. and I know it will cost, im single un married so what else will the disposible income go to?


once again, thank you for the input.
Old Mar 28, 2009 | 12:36 PM
  #35  
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Originally Posted by notorque
and yes, if worked out "properly" higher RPMs will grant more power, or a broader power band, and at the least more time in a lower gear to do more work.
That's not true. Even if you manage to move the power band to where it peaks at 12k, you won't necessarily have a wider power band or more peak power. Having more time in a lower gear means jack squat when you're getting less power in that lower gear.

Higher RPMs != more power.

Originally Posted by notorque
and there are videos all over of cars both with same peak power, one turbo and 8000rpm redline, and an all motor with 12000rpm redline, and the higher end all motor will always beat them.
If that's what you're basing your decision on, then you need to do more research. A higher redline might enable that car to avoid a shift that the other car might have to make in the 1/4 mile. That means very little.

Last edited by Marklar; Mar 28, 2009 at 12:40 PM.
Old Mar 28, 2009 | 02:33 PM
  #36  
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Originally Posted by notorque
not to mention the throttle response you get from NA cant be beat by forced induction. and I know it will cost, im single un married so what else will the disposible income go to?
then drop a N/A 20b in the car and you wont have to worry about moving your readline up to gain a little power
Old Mar 28, 2009 | 02:50 PM
  #37  
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Rotaman from down this way set his rev limiter to 10500 rpm - I told him he was nuts .
Anyway , i've been with him when he revs it out to just under 10,000 . I gotta say it seems to handle it no problem and there still seems to be plenty of power there . He does have intake and freeflow exhaust which I think would be mandatory if you are going to do this .
Old Mar 28, 2009 | 08:34 PM
  #38  
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i wanna see a dyno.
Old Mar 29, 2009 | 03:41 PM
  #39  
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I am starting to believe people on here are the most closed minded I have ever run against who think they know everything. Ive been doing sanctioned racing for almost 10 years now. oh well.
Not many asshats but I'm sure they still believe the world is flat. RX8 owners are SO different than RX7 owners.

So I have done the research, and found that our cars even with increased flow and tuning are useless. forced induction is the only usefull way to get power. NA builds peak out at ~260hp....this is all unless i wanna spend 20 grand....

with this being said, car is being posted for sale locally. Im going back to other makes, where I can spend 5g and end up with 400hp and a lightweight chassis HIGH revving NA build.
Old Mar 29, 2009 | 03:49 PM
  #40  
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Just build a 3-rotor
Old Mar 29, 2009 | 05:46 PM
  #41  
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Originally Posted by notorque
I am starting to believe people on here are the most closed minded I have ever run against who think they know everything. Ive been doing sanctioned racing for almost 10 years now. oh well.
Not many asshats but I'm sure they still believe the world is flat. RX8 owners are SO different than RX7 owners.

So I have done the research, and found that our cars even with increased flow and tuning are useless. forced induction is the only usefull way to get power. NA builds peak out at ~260hp....this is all unless i wanna spend 20 grand....

with this being said, car is being posted for sale locally. Im going back to other makes, where I can spend 5g and end up with 400hp and a lightweight chassis HIGH revving NA build.
I believe you may be mistaken. I'd like to know what car you plan on building. We aren't closed minded, we're realistic.
Old Mar 30, 2009 | 12:23 AM
  #42  
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Originally Posted by notorque
I am starting to believe people on here are the most closed minded I have ever run against who think they know everything. Ive been doing sanctioned racing for almost 10 years now. oh well.
Not many asshats but I'm sure they still believe the world is flat. RX8 owners are SO different than RX7 owners.

So I have done the research, and found that our cars even with increased flow and tuning are useless. forced induction is the only usefull way to get power. NA builds peak out at ~260hp....this is all unless i wanna spend 20 grand....

with this being said, car is being posted for sale locally. Im going back to other makes, where I can spend 5g and end up with 400hp and a lightweight chassis HIGH revving NA build.
yep,

most of us know that. so you did the research after you got the car..

seems with doing sanctioned racing for ten years you would know better..

beer
Old Mar 30, 2009 | 12:47 AM
  #43  
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That video was disgusting... what a buncha hicks
Old Mar 30, 2009 | 01:04 AM
  #44  
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Originally Posted by notorque
I am starting to believe people on here are the most closed minded I have ever run against who think they know everything.

So I have done the research, and found that our cars even with increased flow and tuning are useless. forced induction is the only usefull way to get power. NA builds peak out at ~260hp....this is all unless i wanna spend 20 grand....

with this being said, car is being posted for sale locally. Im going back to other makes, where I can spend 5g and end up with 400hp and a lightweight chassis HIGH revving NA build.
Wow, just saw this post and I'm surprised more at the resistance from yourself, notorque, than I am from everyone else. No offense to you, but the strive for N/A power has been something people have been making since the day the RX8 has hit the market. While I'm not ruling out any new technology developments that might change things, for the most part everything that can be tried HAS been tried.

We have people who have decades of rotary experience here on this board. I'm inclinded to think the RX7 people are more open minded because their understanding of the RENESIS is next to nothing. I, myself, find it a little arrogant that people come onto this board thinking they are going to stumble onto some simple solution to make the RX8 make serious N/A power that we have not already tried or thought about.

It's not that we're closed minded, it's just that we have thought about all the issues and steps you have proposed.

The issue with power generation with the high RPM's of the rotary is a reduction of the volumetric efficiency of the motor. As the motor spins faster, the time for combustion decreases and the amount of air that can get pulled into the motor reduces.

Beyond that, the overall balance of the motor isn't strong enough to handle rotations beyond 10,000 RPM's. Off the top of my head I cannot remember the specific parts that are effected.

As it was mentioned prior, the two things that are needed would be a balanced motor capable of 10,000+ RPM's and larger ports to increase the amount of airflow.

Porting the RENESIS is not impossible, but the overall impact is small because the ports are close to water jackets so extreme porting isn't an option.

Yes, forced induction is the best way to get increased power from the motor without any other major engine modifications and probably the best bang for your buck.

So I have done the research, and found that our cars even with increased flow and tuning are useless. forced induction is the only usefull way to get power. NA builds peak out at ~260hp....this is all unless i wanna spend 20 grand....
Useless is a pretty strong term. My useless car has easily shown up other vehicles twice the value so that claim is pretty baseless.

It's clear you didn't do enough research as your findings are anything but conclusive and it wouldn't take $20,000 to reach your power goals.

with this being said, car is being posted for sale locally. Im going back to other makes, where I can spend 5g and end up with 400hp and a lightweight chassis HIGH revving NA build.
So long!
Old Mar 30, 2009 | 01:08 AM
  #45  
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Originally Posted by notorque

with this being said, car is being posted for sale locally. Im going back to other makes, where I can spend 5g and end up with 400hp and a lightweight chassis HIGH revving NA build.
but how will we cope without your open mind to help us ?????
Old Mar 30, 2009 | 08:24 AM
  #46  
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I thought people researched cars BEFORE they bought them? I guess that was a dying fad.
Old Mar 30, 2009 | 10:25 AM
  #47  
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Ok, so I can assume that the quick little burst to the redline limiter I did last week when I wasnt paying attention to the tach didnt really hurt anything?
I was kinda worried...

Mike
Old Mar 30, 2009 | 11:28 AM
  #48  
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Originally Posted by AlbertaRX-8
Ok, so I can assume that the quick little burst to the redline limiter I did last week when I wasnt paying attention to the tach didnt really hurt anything?
I was kinda worried...

Mike
should be fine. I would try not to push the car past the limiter like that too much, but a couple times shouldn't hurt too much.
Old Mar 30, 2009 | 05:20 PM
  #49  
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Should be alright, our motor's been to 9500 a fair few times and is still healthy, although it is entirely on pre-mix, no OMP.
Old Mar 31, 2009 | 02:05 AM
  #50  
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Originally Posted by notorque
RX8 owners are SO different than RX7 owners. So I have done the research, and found that our cars even with increased flow and tuning are useless. forced induction is the only usefull way to get power. NA builds peak out at ~260hp....this is all unless i wanna spend 20 grand....
well sir, i own many RX-7's and i also own an RX-8. i'm no different than now than a year ago when i didn't have an 8. and as far as the RX-8 being useless, that is a crummy statement. th eRX-8 is a splendid car out of the box. the technology is superb as are the performance peramiters of the vehicle and of its engine. remember, we're dealing with 1.3 litres/80 cubic inches here, not some 454 big block. the renesis msp is different from the "standard" 13B and of course building the engine in the same manner as the older 12A/13B's is different with different power results. forced induction is a great way to make power and a great way to detonate an improperly tuned rotary. i own one of each: a 12A powered 80 Leather Sport, 85 GS with a 13B from a GSL-SE, an 88 10th Anniversary with a 13B which is turbocharged, and an RX-8 with the Renesis MSP. i quite like them all but find the RX-8 the most plesent to drive hard.


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