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Discussion Starter · #1 ·
So the car that I'll be buying on Saturday has about 1,600 Type 1 over rev. How can you get these over revs on PDK car? I'd think that the computer wouldn't allow it with the PDK.
 

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Discussion Starter · #3 ·
Ahhh, it sounds like it's just hitting the rev limits...same deal as with GT3s. I wasn't too concerned about the Type 1 over revs at all...it's once you get to Type 3/4 that is when you begin to get concerned.
 

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I've hit 8000-8200 a bunch of times. No big deal. It's a feature.

My 6MT S4 shifts to 7200-7400 RPM where redline is supposed to be 7000. The DSG versions are total crap, as they force shifts at 6200-6400 RPM.
 

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That's just running into the rev limiter. Really no problem. Each hit is ⅓ of a revolution (so 500 revs @8K rpm or just a few seconds). No worries.
 

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Just curious, OP, but how many miles are on the car? Just wondering how it was (or wasn't, lol) broken in....

P.S. This is not to start a break-in war (again), just to collect another data point as I'm trying to decide how to break mine in myself when it gets here in December (hopefully!).
 

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Yep. It's an engine. It has momentum.
This is a common misconception. Momentum can only cause a continuation of the current state; it cannot accelerate it. It's the same error made by racers who insist that their car accelerated when it hit the wet grass during an off-track excursion.
 

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This is a common misconception. Momentum can only cause a continuation of the current state; it cannot accelerate it. It's the same error made by racers who insist that their car accelerated when it hit the wet grass during an off-track excursion.
I don't think that was the explanation. I quote:

"...[the rev limiter] cuts the gas supply, but it does not turn off the engine.If the engine is accelerating rapidly at red line, the mechanical inertia/momentum will carry it past red line RPMs, even after the fuel supply has been cut off, thereby causing ignitions in the lower rev ranges which are recorded by the DME."

Sounds to me like despite a hard limiter, the RPMs continue a bit because the fuel is not all exhausted.

In any case, no big deal. I'd ignore it. No worries.
 

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When a rocket fires in the air. IF the rocket turns off, does it still gain altitude? yes.

similar situation here, RPM can climb after fuel has been cut off.
 

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As has been posted before, if you're going downhill, you can still accelerate after the fuel has been cut off.
 

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What's the difference between a Type 1, Type 2, and Type 3 overrev?
 

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Example of over rev ranges

"981 ... models have the ability to record ignitions in 6 different ranges. Rev Range 1 and 2 record ignitions at or just below the limiter."

Yes, but does anyone have any specific rpm ranges for the newer engines in the 981's?

I believe the 981 (? engine model designation) M9A1 3.4 liter's official power peak is at 7,400 rpm & "red line" is now @ 7,800 rpm.
I'm not seeing anything newer with a quick Google search on "Porsche M9A1 over rev range" other than the 911virgin.com link.
 

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Yes, but does anyone have any specific rpm ranges for the newer engines in the 981's?

I believe the 981 (? engine model designation) M9A1 3.4 liter's official power peak is at 7,400 rpm & "red line" is now @ 7,800 rpm.
I'm not seeing anything newer with a quick Google search on "Porsche M9A1 over rev range" other than the 911virgin.com link.
No, I don't see any but this is interesting vs the previous generation here. The key differences being the ranges reduced from six to three and the number of relevant hours increased from 50 to 200. Granted this is not the same engine but the information is identical to the 911 website. So I would expect that to protect themselves, Porsche has decreased the number of ranges to three for both the 981/991 engines but that is just a guess with the same idea of 200/300 split between range 1 and 2.
 

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I pulled my over revs using my Durametric last week, car runs great with 58,000 miles on the clock. 583 range one, 21 range two.
 

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I pulled my over revs using my Durametric last week, car runs great with 58,000 miles on the clock. 583 range one, 21 range two.
I only wish there was a diagnostic tool we could buy that could work with the 981. You have a 987, right? Apparently the 981's computer is encrypted and no one has broken the code yet. :(
 

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You are correct as that was the case until recently. The Duametric tool now works with the model 981. I am trying to decide between the the home use version and the commercial version. They have been advertising on their website for some time that the newest version works with 981s.

As far the engine computer software encryption issue as it relates to after market software upgrades it seems to depend on who you ask. At any rate, I have not seen anything for sale yet.

I only wish there was a diagnostic tool we could buy that could work with the 981. You have a 987, right? Apparently the 981's computer is encrypted and no one has broken the code yet. :(
 
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