How to read over rev report?
#19
Rennlist Member
I would not assume tracked because of type 1s
i would also not worry about these type 1s.
i suspect it is pretty easy to get type 1's if car is on boost and hits limiter prior to shifting.
#21
Rennlist Member
You are not reading the report correctly - it says there have been 566 ignitions (not over revs) in range 1 with the last over rev ignition occurring at operating hour 298.78 (so recently since the car has 299.55 hours). You don't know when all the over revs occurred only that the last one was recorded at hour 298.78. 7,000 rpm = 116.7 revolutions per second and there are 3 ignitions per revolution which would give about 350 ignitions every second. Divide that into your 566 ignitions and you get less than 2 seconds of over rev in the lowest range. I doubt this car ever saw a track or if it did it was driven very sedately. This is a very good over-rev report.
#23
Rennlist Member
Less than 2 seconds over 300 hours of operating time is not a worry. Range 1 over revs typically occur when the rev limiter kicks in to protect the engine. As I said, this is a very good report...but don't forget to have a PPI done to possibly disclose any other potential problems. Good luck.
#25
Hi, what is the protocol to read these values ?
Can this be read with OBD2 tool?
I have the Kiwi3 OBD2 tool, on which I can program code to read from the car.
I have regular OBD2 commands for now, but I would be interested on reading and writing more Porsche specific data.
Can this be read with OBD2 tool?
I have the Kiwi3 OBD2 tool, on which I can program code to read from the car.
I have regular OBD2 commands for now, but I would be interested on reading and writing more Porsche specific data.
#26
Rennlist Member
Hi, what is the protocol to read these values ?
Can this be read with OBD2 tool?
I have the Kiwi3 OBD2 tool, on which I can program code to read from the car.
I have regular OBD2 commands for now, but I would be interested on reading and writing more Porsche specific data.
Can this be read with OBD2 tool?
I have the Kiwi3 OBD2 tool, on which I can program code to read from the car.
I have regular OBD2 commands for now, but I would be interested on reading and writing more Porsche specific data.
#28
Racer
Just looking at the table...
Standard Carrera and Turbos capture over rev data from (max RPM+200)
GT3 capture data from (max RPM+600)
Why is 200+ revs the marker for standard cars and 600+ the marker in GT3 cars?
Is it because Porsche engineers expect GT3's to be bouncing off and above the limiters more often and therefore don't want to catch masses of irrelevant data?
Or…
Is this because the GT3 motorsport engine can withstand higher loads/tolerances and therefore does not require the same degree of monitoring/protection as the standard Carrera and Turbo engines?
Standard Carrera and Turbos capture over rev data from (max RPM+200)
GT3 capture data from (max RPM+600)
Why is 200+ revs the marker for standard cars and 600+ the marker in GT3 cars?
Is it because Porsche engineers expect GT3's to be bouncing off and above the limiters more often and therefore don't want to catch masses of irrelevant data?
Or…
Is this because the GT3 motorsport engine can withstand higher loads/tolerances and therefore does not require the same degree of monitoring/protection as the standard Carrera and Turbo engines?
#29
New member here looking at a 2007 Turbo and trying to decipher a DME report using the information provided in this thread above over time. I put the following chart together to try and understand what DME output means. The shaded area is what I think the Ranges are for a 997 and what they mean for the number of revolutions the motor turns per second at the high end (worst case) of the range (for purposes of this analysis I added the top end of the Range 6 at 9,800, but technically Range 6 is just recording ignitions above 9,000 RPM). The next column is from the DME output for the car I am looking at, which shows the number of recorded ignitions within each Range. The odd thing is the single ignition shown in both Range 5 & Range 6 which would seem an impossible reading and I would appreciate any insight anyone can provide.
Next I tried to calculate the total engine time in seconds that the motor has spent in each range. If I did this right, it looks like 22 seconds in an over-rev between 6,800-7,000 RPM range, 3.9 seconds in the 7,000-7,200 RPM range, .5 seconds in the 7,200-7,400 RPM range and then some very hard to measure moments in ranges 4-6.
Can anyone comment on whether I made these measurements properly and how concerned I should be about the recordings in Ranges 4-6?
Thank you.
Next I tried to calculate the total engine time in seconds that the motor has spent in each range. If I did this right, it looks like 22 seconds in an over-rev between 6,800-7,000 RPM range, 3.9 seconds in the 7,000-7,200 RPM range, .5 seconds in the 7,200-7,400 RPM range and then some very hard to measure moments in ranges 4-6.
Can anyone comment on whether I made these measurements properly and how concerned I should be about the recordings in Ranges 4-6?
Thank you.