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Discussion Starter #1
I was out with a few friends and we got into a friendly race. I had killed him once but he wanted a second chance. Around 70-80mph I drop it into 3 and we are off. I'm killing him once again but wanted to ride out the gear and then go into 4th. I rode out 3rd gear and hit the rev limiter and the shifted into 4th. Ran 4th for a second, got off the throttle and hit the up button on my afc to see what I was boosting at. Come to find 3rd gear ran up to 8600rpms. BTW, my stock tach is still not working which is why I resorted to the afc.



As far as I know my head is still all in working condition thankfully. But why didn't the ecu do its job and cut me off at 7500rpms?
 

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:wtf: unless the AFC is somehow off... upgraded ecu?
 

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Acting my age
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Change your AFC from 12 cyl to 6 and stop shifting at 4300 rpms!!

j/k.. I've seen this sorta thing before on MK4's.. The ignitor somehow spikes the signal.. On one of my MK4 dynos the RPM at the revlimiter spiked and added like 2" of dead column to my dyno sheet.. Hopefully your reading was just a fluke and you didnt rev it that high with the stock ECU cuz there wouldnt be any fuel map up there! :D

But 4sure save that pic :)
 

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Discussion Starter #4
I guess it would have to be the afc is off or the signal from the ignitor spiked. And without any fuel maps I would be in some pretty big trouble. Hopefully this was a freak think and it will not happen again.
 

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Moderator, Aight Peace
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It is most likly due to you dropping down the gear to 3rd from 70 - 80mph that the sudden jump that the ECU just let it go on, at least thats what I think happened cause I can take my 7m up to 7500rpm without hitting no limiter if I drop the gear down at a high enought speed and when I had a honda it use to do the same thing... aight peace :chicken:

btw, why are you racing without a tach???
 

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Discussion Starter #6 (Edited)
The afc reads the tach signal and its viewable. many different attempts were made to get the stock tach to work and even burnt up an igniter. for now I have given up on that until I get some more ambition to deal with its frustrations.

I drop it into 3rd gear all the time on the high way for little races. never once have I had this occurrence. It probably had to do with me hitting the rev limiter at the end of 3rd and then quickly shifting into fourth. Shifting into 3rd gear on the highway only puts me around 4500rpms, which I normally sit at for a few seconds. So I’m not totally shocking the ecu and taking of right away.
 

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Madd Tyte JDM yo ®
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i hope you dont break it... not too many people around here that can fix it...

who were you racing?
 

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A fella on on australian forum had an auto 1jz in a cressida and was trying to drift. It dropped down a gear and when he checked his SAFC it read 10900rpm! AFAIK no damage occured as it was only a very small amount of time. He posted the pic also. Pretty crazy :)
 

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wow i cant imagine what 11k rpms sounds like on a 1j...
 

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oh you mean like alanis moresette in dogma? :)
 

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Discussion Starter #14
BoostAddctn said:
Sounds like a Honda... aight peace
I have actually had a cop tell me mine sounded like a weed wacker and this was at low rpms :(




eli thanks for the picture. I went to grab my camera and I left the freaking battery at home....


flubyux I have the mechanics under control. And I was racing Jayson.
 

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I know I read a post on here saying that the stock ecu had a higher rev limiter at higher speeds. I distinctly remember reading that it went up to 8500rpm. Not sure if whoever posted that info was right...

But, whether he was right or not, at those speeds a rev limiter that wasn't extremely aggressive could have trouble forcing the car to slow down. It might even have trouble keeping the car from continuing to accelerate a bit. When you were bouncing off the limiter, did it feel like the car was really slowing down, like decreasing significantly in speed? Or was it a smoother feeling, like you were accelerating much less hard or not at all, but not really slowing down? If it was either of the latter two I mean the rev limiter just wasn't doing enough. And the whole "bouncing" thing means it operates on feedback, cycling between a higher and a lower rpm, within which is the target "cutoff" rpm. I've never been in a fast car that had a real hard rev limiter. Usually you just kinda bounce off it but the car keeps going. It's not a big deal I don't think.

Shiva
 
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