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Redline pass 9k?

Old Aug 13, 2010 | 10:14 AM
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Redline pass 9k?

I have a 2010 R3, I finally pushed it to redline after 4,000KM.

I found that the speedo went pass 9k rpm. I am 99% sure it did.

I also didn't hear the redline beep? I was driving with windows open, maybe I missed the beep.

Just me or others can vertify?
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Old Aug 13, 2010 | 10:16 AM
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Originally Posted by kenken3686
I have a 2010 R3, I finally pushed it to redline after 4,000KM.

I found that the speedo went pass 9k rpm. I am 99% sure it did.

I also didn't hear the redline beep? I was driving with windows open, maybe I missed the beep.

Just me or others can vertify?
With the windows open and the Renesis screaming, the beep is easy to miss. A more valid test would be with the radio off and windows shut.

As far as redline, I think the fuel cut off is just past 9000. Did the needle bounce off the fuel cut or just proceed until you pushed the clutch in?
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Old Aug 13, 2010 | 10:17 AM
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yeah the redline is 9K but the fuel cut isnt until 9500 rpm or so. The engine could spin to 15K or higher no problem. It's the transmission and clutch and stuff that can't handle it.

I dropped my rx8 into second rather than 4th at over 100 mph and the tach went way past 10K almost to the speedo. scared the carp outta me, but the car was fine,
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Old Aug 13, 2010 | 10:19 AM
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Originally Posted by Aseras
yeah the redline is 9K but the fuel cut isnt until 9500 rpm or so. The engine could spin to 15K or higher no problem. It's the transmission and clutch and stuff that can't handle it.

I dropped my rx8 into second rather than 4th at over 100 mph and the tach went way past 10K almost to the speedo. scared the carp outta me, but the car was fine,
LOL ... did you fire out the apex seals, your tranny off the housing, and the cat off the downpipe????? jeeeez
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Old Aug 13, 2010 | 10:26 AM
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nothing happened at all besides the fuel cut and a heart attack. If I hadn't hit the fuel cut and had the car slow down it wouldn't have even known I revved it that high. It went into gear just as smooth as ever and the car sounded just as loud.

I did that when my car was young, in the 20K range IIRC. I'm over 108K now. Still waiting to hear if my car is back from the shop. Hit a pig.
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Old Aug 13, 2010 | 10:53 AM
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Your lucky the flwheel didn't come through the floor board and cut off your legs
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Old Aug 13, 2010 | 12:12 PM
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ken: it is possible to keep going past 9,000 rpm but there really is no point as most RX-8's make their peak power below 9k. Pushing the engine that far just puts unnecessary stress on the components.

Happy Rotoring
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Old Aug 13, 2010 | 12:16 PM
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Oh I was just wondering why it went pass it. =)
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Old Aug 13, 2010 | 12:16 PM
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Going past 8600 rpm is pointless unless you need the extra rpm to delay the shift.
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Old Aug 13, 2010 | 12:20 PM
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Peak power is i think in the 7-8k range i believe. I know fuel cut off comes at 9750 i believe. I've pushed the needle close to the 10 mark. But the car was bogging from the fuel cut off. There really is no need to push to the beep unless you are showing off that your car beeps. Shift at redline and be a good person.

I think the 747B from the le mans ran in the low teens k rpm. What most people do not understand is that the rotary is designed for high rpms hence why it revs up so high.
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Old Aug 13, 2010 | 01:55 PM
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Originally Posted by Aseras
yeah the redline is 9K but the fuel cut isnt until 9500 rpm or so. The engine could spin to 15K or higher no problem. It's the transmission and clutch and stuff that can't handle it.

I dropped my rx8 into second rather than 4th at over 100 mph and the tach went way past 10K almost to the speedo. scared the carp outta me, but the car was fine,

Thats crazy !!! LOL
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Old Aug 13, 2010 | 01:58 PM
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Ive passed 9k many times, no problem at all. still has power. sounds great.
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Old Aug 13, 2010 | 02:31 PM
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Originally Posted by Aseras
yeah the redline is 9K but the fuel cut isnt until 9500 rpm or so. The engine could spin to 15K or higher no problem. It's the transmission and clutch and stuff that can't handle it.

I dropped my rx8 into second rather than 4th at over 100 mph and the tach went way past 10K almost to the speedo. scared the carp outta me, but the car was fine,
SAME EXACT thing happened to me. My brother was test driving my car (he owns a 383 stoker vette, Challenger, and owned a 350Z, over 35 years old with kids; in no way a novice driver).

He accidently downshifted into 2nd instead of 4th and the tach was in the speedometer area. Scared the **** out of me but 4 years later, it obviously didnt do any damage lol.
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Old Aug 13, 2010 | 02:34 PM
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Originally Posted by mysql101
Going past 8600 rpm is pointless unless you need the extra rpm to delay the shift.
When I put my car on the dyno it was still holding power at 9000rpm like a champ so I see no reason why you shouldn't take it that high. Now if power is drastically dropping off at 8,600rpm I could understand but I didn't see that on my car.

On a high-revving car you want the most average power in each gear if you're all about speed. Shifting the second you're at peak power seems like you're selling yourself short if you ask me considering the rotary appears to hold power pretty well once it is at that point. I'd think holding off another 300-400rpm (after peak horsepower) would keep the average power numbers higher. That's all in theory though of course. lol

Last edited by RWatters; Aug 13, 2010 at 02:36 PM.
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Old Aug 13, 2010 | 02:50 PM
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There are several reasons that increasing the rev limit past 9k (or whatever it is actually at from variances) is generally not something to do lightly:

1 - Beyond about 7,500rpm, the heat being generated starts climbing sharply. One reason is the OEM water pump (2004-2008) isn't well designed for high RPM. It is also simply alot of fuel being burned. The OEM cooling system isn't well designed to handle this heat for very long, so 9k is about as far as you want to go
2 - 9k is about the limit where the transmission casing will hold the gears inside of it if something breaks. Passing 9k RPM is when people start getting kevlar shields to protect the driver /passenger from dismemberment and death from gears or other parts being turned into flying saw blades.
3 - Some race teams report that the tips of the rotors CAN start to contact the housing past 9k or so, some claim it happens even earlier. They have never posted pictures or any other proof, so it is still text claims and can be taken with a grain of salt, as they may have built closer tolerances that are getting exceeded.
4 - Transmission fluid heats up with RPM, from both the exhaust running right next to it and from the heat generated from the spinning gears. Overheating the transmission fluid is already something that can happen over about 8k RPM, which is why one reason you shouldn't hold it there, but increasing the rev limit will increase the amount of time you are building the heat fast, and too much of it and your transmission will get toasted.
5 - The ECU isn't tuned for anything over 9k rpm, and the intake and exhaust ports are sized and mechanically tuned for up to 9k. Going over 9k is leaving the boundries of where the existing setup was designed for. Port redesign isn't really viable for the Renesis, though the ECU mapping can be adjusted/added to.


If you want to address each of these points, I've heard that Mazda got the engine (not in a car) up to 15,000 rpm. Take that with a grain block of salt too though.
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Old Aug 13, 2010 | 03:01 PM
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Originally Posted by RIWWP
There are several reasons that increasing the rev limit past 9k (or whatever it is actually at from variances) is generally not something to do lightly:

1 - Beyond about 7,500rpm, the heat being generated starts climbing sharply. One reason is the OEM water pump (2004-2008) isn't well designed for high RPM. It is also simply alot of fuel being burned. The OEM cooling system isn't well designed to handle this heat for very long, so 9k is about as far as you want to go
2 - 9k is about the limit where the transmission casing will hold the gears inside of it if something breaks. Passing 9k RPM is when people start getting kevlar shields to protect the driver /passenger from dismemberment and death from gears or other parts being turned into flying saw blades.
3 - Some race teams report that the tips of the rotors CAN start to contact the housing past 9k or so, some claim it happens even earlier. They have never posted pictures or any other proof, so it is still text claims and can be taken with a grain of salt, as they may have built closer tolerances that are getting exceeded.
4 - Transmission fluid heats up with RPM, from both the exhaust running right next to it and from the heat generated from the spinning gears. Overheating the transmission fluid is already something that can happen over about 8k RPM, which is why one reason you shouldn't hold it there, but increasing the rev limit will increase the amount of time you are building the heat fast, and too much of it and your transmission will get toasted.
5 - The ECU isn't tuned for anything over 9k rpm, and the intake and exhaust ports are sized and mechanically tuned for up to 9k. Going over 9k is leaving the boundries of where the existing setup was designed for. Port redesign isn't really viable for the Renesis, though the ECU mapping can be adjusted/added to.


If you want to address each of these points, I've heard that Mazda got the engine (not in a car) up to 15,000 rpm. Take that with a grain block of salt too though.
if they set the redline to 9k, Id say mechanically its good for another 2-3k otherwise this car wouldntve lasted 6 years of driving.
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Old Aug 13, 2010 | 03:03 PM
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Originally Posted by RWatters
When I put my car on the dyno it was still holding power at 9000rpm like a champ so I see no reason why you shouldn't take it that high.

https://www.rx8club.com/series-i-tech-garage-22/dyno-results-compilation-77031/
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Old Aug 13, 2010 | 03:07 PM
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Originally Posted by jasonrxeight
if they set the redline to 9k, Id say mechanically its good for another 2-3k otherwise this car wouldntve lasted 6 years of driving.
True, but RIWWP makes some good points as to why we should just leave it where it's at. Too many people assume that if their redline is higher, they'll produce more power, which isnt true. The only benefit is that when you upshift youll land at a higher RPM in the next gear.
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Old Aug 13, 2010 | 03:12 PM
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One thing I didn't mention, that most people forget, is that you can only reasonably tune a car (both electronic ECU and physical airflow tuning) for a set RPM range. One reason we have issues down low is that we can go so high. As you move the rev limit up, your low end starts to suffer more and more and more, to the point of having to have really high idle speeds, etc...


Abel Ibarra's RX-7 20b idles at 5,000rpm, because it is tuned to run so high that it can't idle lower than that. And extreme example, but the higher you go, the more low end has issues.

I expect the next rotary design will have a decrease of revs, if for no other reason than to improve the bottom end (even if it is through a longer "stroke" which increases rotational pull that makes higher revs harder to design for)
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Old Aug 13, 2010 | 03:51 PM
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Correct me if I'm wrong, but I posted a similar question a while back when I saw my tach go to well over 9,000, and the responses were overwhelming that the tach is highly inaccurate at high RPM during hard acceleration. According to Racing Beat on the web page for their ECU reflash, they state that the fuel cutoff is 9,000 stock, and 9,300 after their flash. Everything I've read indicates OEM fuel cutoff is at 9,000 RPM, and if you see your tach go higher than that, it's tach error.
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Old Aug 13, 2010 | 03:54 PM
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the tach can be off by as much as 500 rpm
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Old Aug 13, 2010 | 04:05 PM
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Originally Posted by Jedi54
the tach can be off by as much as 500 rpm
This is true, just like how speedometers can vary by a couple MPH. Also, if you add mods that make your car rev faster, there's also a chance that your motor will rev just a tad faster than the RPM needle reflects; in otherwords, itll be playing catch up.

However, I havent really heard of that on RX8's too much, my brothers 500WHP vette has that problem though lmao...
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