2011 GTS PDK DME Rev Ranges Observed
08-04-2013, 09:04 AM
#32
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Once the rev limiter is reached, the software diminishes the flow of fuel to the engine. It does not completely stop the flow of fuel to the engine.
08-04-2013, 10:52 AM
#33
That said, if the rev limiter works by cutting the fuel, there will be a delay between the time the fuel is cut and the engine stops firing, due to residual charge in the intake plenums.
11-06-2014, 11:54 PM
#36
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Below are the six "rev ranges" for the 997.2.
Rev range 1: 7,500 to 7,699 = Maximum permitted engine speed exceeded; engine damage possible.
Rev range 2: 7,700 to 7,899 = Maximum permitted engine speed exceeded; engine damage possible.
Rev range 3: 7,900 to 8,099 = Maximum permitted engine speed exceeded; engine damage possible.
Rev range 4: 8,100 to 8,399 = Maximum permitted engine speed clearly exceeded; engine damage probable.
Rev range 5: 8,400 to 8,899 = Maximum permitted engine speed very clearly exceeded; engine damage very probable.
Rev range 6: over 8,900 = Engine damage has generally occurred.
Rev range 2: 7,700 to 7,899 = Maximum permitted engine speed exceeded; engine damage possible.
Rev range 3: 7,900 to 8,099 = Maximum permitted engine speed exceeded; engine damage possible.
Rev range 4: 8,100 to 8,399 = Maximum permitted engine speed clearly exceeded; engine damage probable.
Rev range 5: 8,400 to 8,899 = Maximum permitted engine speed very clearly exceeded; engine damage very probable.
Rev range 6: over 8,900 = Engine damage has generally occurred.
11-07-2014, 12:05 AM
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Even if is is activated at 7,500 RPM, you have already entered rev range 1 and will have ignitions (a.k.a. over revs) in rev range 1.
11-07-2014, 01:14 AM
#38
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I think a few of you are getting hung up on semantics. The DME report is a histogram of engine ignitions, broken down into specific ranges. If Range 1 is at or below the redline, they're not "over revs". It merely indicates the engine has been run up to and against the rev limiter.
Previous Porsches have had two rev limiters, a Soft and a Hard. When you hit the soft limit, the engine would intermittently cut the spark. It felt like a high speed miss. When you hit the hard, it fully cut the spark and the engine felt like it hit a wall. It was very abrupt. Bouncing off this hard limit seemed to me to be abusive to the engine. If you kept at it, the engine felt like it was taking a pounding.
If you've got a PDK, relax. You're not going to dangerously over speed the engine.
Previous Porsches have had two rev limiters, a Soft and a Hard. When you hit the soft limit, the engine would intermittently cut the spark. It felt like a high speed miss. When you hit the hard, it fully cut the spark and the engine felt like it hit a wall. It was very abrupt. Bouncing off this hard limit seemed to me to be abusive to the engine. If you kept at it, the engine felt like it was taking a pounding.
If you've got a PDK, relax. You're not going to dangerously over speed the engine.
11-08-2014, 06:13 PM
#39
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Nor sure if the Range 1 shown above applies to my 2009 S. If so, then it is over rev as the redline is 7400 while the range starts at 7500.
