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What is Max RPM before failure

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Old Mar 27, 2009 | 02:56 AM
  #1  
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What is Max RPM before failure

ive searched and so far the max RPM I have found anyone go to on here is 9500RPM.
reason asking is my brothers old civic type-r with Spoon valvetrain/forged internals made it to 11500RPM (still making power) all day long before he sold it. With that being said I hear our motors are "smoother" and this makes me think higher is easier.

Is it possible for our motors to go to a higher RPM than 9500rpm?

If anyone has done it, how high did they go and what were the repercussions of long time exposure to high RPM?

Also how was this higher RPM obtained?



if there is already a thread with this answered please point me in the right direction as to searching at 3am isnt too conducive to my thought process.

Last edited by notorque; Mar 27, 2009 at 02:59 AM.
Old Mar 27, 2009 | 03:37 AM
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10k RPM
Old Mar 27, 2009 | 03:52 AM
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Yes you can shift pas that but you have to have a tune on it like the Cobb AP or InterX. They will let you remove the rev limiter on the AT and MT.
Yes rev that bitch and enjoy it. The car was made to do it. Get hot burn and pass carb build up.
-Gil
Old Mar 27, 2009 | 05:11 AM
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its called apex seal chatter. overrevving on a stock port with stock seals is not a good idea. the engine isnt making more than peak horsepower over redline anyways. this chattering will not only ruin the apex seals, but they can quickly score the housings. the omp cannot keep up with the overrevving and thus due to the lack of lubrication at higher than specified engine speeds, abnormal wear and chatter marks can occur. a properly prepped rotary, renesis and 12A/13B alike will happily rev beyond 10Krpm when properly ported and equipped with the proper apex seal/side spring/ hardened stationary gearset/ premix combo. the engine will make peak power in that rpm range. bottom line, the rev limiter is there for a reason.

Last edited by mazdaverx7; Mar 27, 2009 at 05:19 AM.
Old Mar 27, 2009 | 05:15 AM
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Thanks for that. I would like for other that have been running ther 8 with out a rev limiter to talk about their experience with this on and off the track. Good info.
Old Mar 27, 2009 | 08:45 AM
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I don't understand why you are comparing a heavily modified Honda engine to a basically stock Renesis.
Old Mar 27, 2009 | 08:51 AM
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Pointless.... Not to mention increased wear rate.
Old Mar 27, 2009 | 09:04 AM
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I read somewhere that the engine could go right up to 13k...but at that point "harmonic distortion" would destroy the engine. Good point about the wear. I would definitely think about potential cost vs. benefit on this one.
Old Mar 27, 2009 | 09:20 AM
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I dropped my car into 2nd gear at over 100mph once ( and it was buttery smooth too ). Tach goes right past 10K almost to the digital display. Never had a issue with the car, and I did that when it was newer. It's been 3 years since then.

Keep in mind the rotary internals operate at 1/3 rpm. so while the driveshaft might be doing 10K, the rotors are only turning at 3k IIRC.
Old Mar 27, 2009 | 09:37 AM
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Originally Posted by arghx7
I don't understand why you are comparing a heavily modified Honda engine to a basically stock Renesis.
same reason people compare modded econo-cars to stock sports... Ego. They want to be able to say, "See!!!! I put $X,000s of dollars and made it better than you sports car! HA!!!! ME > You"

what they fail to realize is the "i put $X,000s" to make their eco-car better than a sports car.

I've seen video footage of a HYUNDAI ACCENT beating a Z06 in a drag race. does that mean that shitbox on wheels is better than the vette? nope. just means some numb-nut spent an excessive amount of money on a shitbox on wheels.

Think of it like this: You can gold plate dogshit. but at the end of the day, it's still dog ****.

Last edited by Shinka_MJR; Mar 27, 2009 at 09:40 AM.
Old Mar 27, 2009 | 09:55 AM
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the renesis is balanced to 13,000 rpm.

but:
1. the tranny cant take that. do you want a flywheel bouncing out of the bellhousing and potentially sawing off your legs?
2. the engine cant get enough air in at those rpms and power will really drop off.

so its pointless.
Old Mar 27, 2009 | 10:01 AM
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Originally Posted by mazdaverx7
its called apex seal chatter. overrevving on a stock port with stock seals is not a good idea. the engine isnt making more than peak horsepower over redline anyways. this chattering will not only ruin the apex seals, but they can quickly score the housings. the omp cannot keep up with the overrevving and thus due to the lack of lubrication at higher than specified engine speeds, abnormal wear and chatter marks can occur. a properly prepped rotary, renesis and 12A/13B alike will happily rev beyond 10Krpm when properly ported and equipped with the proper apex seal/side spring/ hardened stationary gearset/ premix combo. the engine will make peak power in that rpm range. bottom line, the rev limiter is there for a reason.
Got a few things to add to this:
Balance the rotating assembly as one and remove as much weight as you can. Think about snap rings.
Might need to underdrive the water pump.
Old Mar 27, 2009 | 10:02 AM
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From: Misinformation Director - Evolv Chicago
Originally Posted by kersh4w
the renesis is balanced to 13,000 rpm.
I don't think I'd trust the Renesis to 13K as is out of the box.
Old Mar 27, 2009 | 10:03 AM
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This is stupid. Power starts dropping off before redline, there is absolutely no reason to want to rev higher unless you have made modifications that move the power band into a higher RPM range. Just wanting to rev a stock Renesis over the rev limiter is stupid and pointless.

Who gives a damn what some highly modified short-stroke Honda engine can rev to? That has nothing to do with the Renesis, apples vs. oranges.
Old Mar 27, 2009 | 10:09 AM
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Originally Posted by Red Devil
I don't think I'd trust the Renesis to 13K as is out of the box.
why? carbon buildup is not an issue at 13k rpm.

and ty marklar for reinforcing whats really important about this.
Old Mar 27, 2009 | 10:32 AM
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Originally Posted by Marklar
This is stupid. Power starts dropping off before redline, there is absolutely no reason to want to rev higher unless you have made modifications that move the power band into a higher RPM range. Just wanting to rev a stock Renesis over the rev limiter is stupid and pointless.
yes stock if you only remove the limiter. as those who have had the RB flash know there is more power to be had lifting the limit if you tune it properly.
Old Mar 27, 2009 | 10:57 AM
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this thread brings to mind the below video, anyone want to duplicate this with a Renesis??

http://www.youtube.com/watch?v=kO3lSTO8uWg
Old Mar 27, 2009 | 11:23 AM
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That video SUCKS... I don't know anything yet... but I'm pretty positive it was only the overheating that killed it... not the sustained RPMs... I wonder how long it COULD last... with a motor that's running well...
Old Mar 27, 2009 | 11:29 AM
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wouldn't sustained high rpm cause the overheating....? I dont think that would be a matter of an engine that is running well but a properly sized cooling system
Old Mar 27, 2009 | 11:43 AM
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Originally Posted by expo1
this thread brings to mind the below video, anyone want to duplicate this with a Renesis??

http://www.youtube.com/watch?v=kO3lSTO8uWg
i know right thought the same thing

Originally Posted by theSLEEPERX8
That video SUCKS... I don't know anything yet... but I'm pretty positive it was only the overheating that killed it... not the sustained RPMs... I wonder how long it COULD last... with a motor that's running well...
it was because they had drained the oil
Old Mar 27, 2009 | 01:47 PM
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OP's brother reminded me of a chance encounter with a young chap and his baby blue Honda Civic. He told me he put int $60k in the car and showed me a bunch of plastic trophies. I then asked, for that kinda money why not get an M3 or something nicer? I guess he realised that I wasn't impressed at all with his Honda Civics and plastic trophies.
Old Mar 27, 2009 | 02:13 PM
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Yeah, It's like walking upto an Audi R8 owner and saying.

Yo, I got a 20B dropped in my RX-8, and all carbon fiber body, I'd SMOKE you in a race!

He could give less of a damn.
Old Mar 27, 2009 | 02:20 PM
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that video was hilarious. The one guy saying "I feel like a fireman" made me laugh. lol no **** the exhaust manifold and piping was glowing. good grief. But did the engine fail from sustained RPM or overheating (which i realize is caused by sustained rpm but not quite the same thing).

regardless, that definitely shows the potential the engine has for durability.

*note: i said potential. this does not however apply to all instances... as it's simply that, potential.
Old Mar 27, 2009 | 03:20 PM
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I missed the part zoom pointed out, with the oil being drained... that was probably what caused most of the overheating there
Old Mar 27, 2009 | 03:22 PM
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why do rotaries fail? carbon buildup.

you think carbon buildup is a problem doing 9k rpm @ WOT?


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