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      03-19-2017, 06:29 PM   #1
distinctperson
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Setting rev limiter

What is the purpose of redlining the car when power peaks at roughly 6k rpm ? Is there something that I am missing ?

Therefore, assuming that there is no purpose in revving the car past its peak power RPM, is there a way to set the limiter to around 6k RPM or so ?

I looked on this forum everywhere but couldn't find a comparable question/post. Thanks!
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      03-19-2017, 07:44 PM   #2
paris1
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Well the first thing that comes to mind is why would you want your engine to hit a rev limiter (be it fuel shut off or electronic) at peak power. Rev limiters can be a rather jarring reminder that you need to shift or back off. Why not just watch the tach and avoid having the engine fall on its face when it hits the imposed cutoff?
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      03-19-2017, 08:14 PM   #3
Vetracr
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I installed a shift light so I could concentrate on track without having to look at tach. You want your eyes on track not gauges. I can adjust rpm light goes on. I set mine at 6500 rpm. Ideally you want to shift at rpm that places engine rpm in next gear up at max torque rpm.
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      03-19-2017, 10:30 PM   #4
distinctperson
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Well, I was thinking that in lieu of a gauge light (which is the next best thing), and to also solve the problem of unnecessarily redlining accidentally when flooring, that the RPM would not climb farther than just a bit above peak torque threshold. I don't feel like this limits the vehicle in anyway at all; rather, this optimizes the vehicle especially in automatic mode where vehicle upshifts at the optimal RPM instead of unnecessarily going to redline and then upshifting (and yes, I know this can be mitigated by shifting manually, but I am obviously looking to automate this process IF POSSIBLE)

EDIT: Ideally, it would also hold that peak RPM instead of cutting fuel in manual mode, and automatically upshifting if left in automatic mode.
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      03-20-2017, 04:50 PM   #5
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I suppose auto shifting at slightly after peak power is better than shifting AT peak power since there is still peak power and high RPMs.

How many RPMS are there after peak power? And then I suppose where does the rpms land after the shift for the next gear is a factor.
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      03-20-2017, 05:34 PM   #6
distinctperson
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Quote:
Originally Posted by NoQuarter View Post
I suppose auto shifting at slightly after peak power is better than shifting AT peak power since there is still peak power and high RPMs.

How many RPMS are there after peak power? And then I suppose where does the rpms land after the shift for the next gear is a factor.
Do you see merits in my pursuit here ? or do you think this is a total waste of time and effort ?
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      03-22-2017, 02:59 AM   #7
distinctperson
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BUMP........ I'm surprised no one is displaying any interest in this.
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      03-22-2017, 04:15 PM   #8
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It is just low value I think.

If I raced it I would not want anything auto shifting and on the street it is a pointless change with risk of unintended consequences not worth troubleshooting.
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      03-22-2017, 09:36 PM   #9
distinctperson
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Let me list the pros and cons of setting the limiter to just a bit above peak torque for each gear as I see them, assuming implementation is possible.

Pros:
1) Engine always stays within the relatively safe RPM range, i.e: never unnecessarily crossing beyond a bit above peak RPM when flooring it (be it in manual mode or auto mode)
2) As a result of step 1, vehicle always stays at peak torque when floored without intervention (as opposed to either intervening manually to upshift once crossing peak torque or losing torque for a period of time until reaching redline before vehicle auto-upshifts.)
3) Launch Control times are further improved as a result of step 1 and 2 (status quo pushes each gear to redline before up-shifting, allowing vehicle to lose torque for each gear before auto-upshift at redline.)
5) Allows you to hold peak RPM when flooring vehicle automatically upshifting in manual mode, or upshift at just after peak torque into next gear's peak torque if left in automatic (major plus.)
4) Because vehicle is never redlined in this fashion, you feel RELATIVELY less guilty when flooring it.
5) It is a software modification, therefore I presume implementation doesn't require any hardware and should be very cheap, if not free.

Cons:
1) Software malfunction or glitch/improper implementation may backfire and allow you to over-rev leading to potential engine damage if pushed beyond redline.

I couldn't think of any other cons actually, and I believe that could be mitigated with proper testing and implementation. Am I missing anything here ? Does this still sound like an unattractive proposition ?
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