Who has a supercharger on an S2 (or 968)?
02-19-2010, 03:43 PM
#32
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Hi Peter. Is the Vitesse piggyback part of the Vitesse MAF kit? Is it set up just to adjust the signal from the MAF? Presumably the 968 kit (unlike the S2 kit) doesn't contain a MAF as it uses the 968 MAF.
When I spoke with Vitesse they indicated they could provide an S2 MAF and have it tuned to suit a supercharger with a given psi out of the box. That seemed ambitious to me, as I would have thought that sort of installation would only work through live tuning on a dyno. Perhaps that only applied to the initial tune? I have heard a lot of positive things about Vitesse, but I guess I'm missing some details, and it's in my nature to question everything and require evidence - comes with being an engineer I guess.
Have you found it has taken a lot of tuning to get it right?
When I spoke with Vitesse they indicated they could provide an S2 MAF and have it tuned to suit a supercharger with a given psi out of the box. That seemed ambitious to me, as I would have thought that sort of installation would only work through live tuning on a dyno. Perhaps that only applied to the initial tune? I have heard a lot of positive things about Vitesse, but I guess I'm missing some details, and it's in my nature to question everything and require evidence - comes with being an engineer I guess.
Have you found it has taken a lot of tuning to get it right?
Since, no 2 engines are alike, we offer the PB to allow the user to fine tune his car the extra 3-5% to get the most out of the engine.
02-19-2010, 03:51 PM
#33
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When going to a forced induction setup, the MAF or AFM sensors generate a different voltage than when in NA form. Both 944S2 and 968 will detect this (as well as other conditions), and will trigger limp mode. It is possible to be in limp mode without having the check engine light come on. I personally do not consider limp mode ignition and fueling to be safe for a forced induction application.
02-26-2010, 10:32 AM
#34
Burning Brakes
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John,
Back when I was running the Apexi unit that SFR supplied as a piggy back the car would run with the CEL on and have a surging idle with poor fuel milage. It ran this way with the MAF plugged in or unplugged. Plus no matter what I did to the settings on the Apexi nothing would change on my Zeitronix readings. The CEL was for a MAF fault and I verified that the wiring for the MAF relocation was correct and the wiring installation for the Apexi was correct for the wiring directions supplied.
I have since gone away from the Apexi and went with a second hand SMT6 and have been attempting to tune a map myself. It is close but still not perfect, but much better than before. It just needs a little more tuning.
Back when I was running the Apexi unit that SFR supplied as a piggy back the car would run with the CEL on and have a surging idle with poor fuel milage. It ran this way with the MAF plugged in or unplugged. Plus no matter what I did to the settings on the Apexi nothing would change on my Zeitronix readings. The CEL was for a MAF fault and I verified that the wiring for the MAF relocation was correct and the wiring installation for the Apexi was correct for the wiring directions supplied.
I have since gone away from the Apexi and went with a second hand SMT6 and have been attempting to tune a map myself. It is close but still not perfect, but much better than before. It just needs a little more tuning.
02-26-2010, 02:29 PM
#35
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John,
Back when I was running the Apexi unit that SFR supplied as a piggy back the car would run with the CEL on and have a surging idle with poor fuel milage. It ran this way with the MAF plugged in or unplugged. Plus no matter what I did to the settings on the Apexi nothing would change on my Zeitronix readings. The CEL was for a MAF fault and I verified that the wiring for the MAF relocation was correct and the wiring installation for the Apexi was correct for the wiring directions supplied.
I have since gone away from the Apexi and went with a second hand SMT6 and have been attempting to tune a map myself. It is close but still not perfect, but much better than before. It just needs a little more tuning.
Back when I was running the Apexi unit that SFR supplied as a piggy back the car would run with the CEL on and have a surging idle with poor fuel milage. It ran this way with the MAF plugged in or unplugged. Plus no matter what I did to the settings on the Apexi nothing would change on my Zeitronix readings. The CEL was for a MAF fault and I verified that the wiring for the MAF relocation was correct and the wiring installation for the Apexi was correct for the wiring directions supplied.
I have since gone away from the Apexi and went with a second hand SMT6 and have been attempting to tune a map myself. It is close but still not perfect, but much better than before. It just needs a little more tuning.
The PB will help, but you could still trigger a fail safe mode. The fail safe with CEL are easy to identify, however the undocumented where no CEL is triggered are the ones to worry about.
With the correct software, the PiggyBack should only be used for minor fine tuning.
BTW. The initial CEL problem you encountered has nothing to do with the wiring.
12-24-2010, 06:45 AM
#36
Three Wheelin'
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John,
Back when I was running the Apexi unit that SFR supplied as a piggy back the car would run with the CEL on and have a surging idle with poor fuel milage. It ran this way with the MAF plugged in or unplugged. Plus no matter what I did to the settings on the Apexi nothing would change on my Zeitronix readings. The CEL was for a MAF fault and I verified that the wiring for the MAF relocation was correct and the wiring installation for the Apexi was correct for the wiring directions supplied.
I have since gone away from the Apexi and went with a second hand SMT6 and have been attempting to tune a map myself. It is close but still not perfect, but much better than before. It just needs a little more tuning.
Back when I was running the Apexi unit that SFR supplied as a piggy back the car would run with the CEL on and have a surging idle with poor fuel milage. It ran this way with the MAF plugged in or unplugged. Plus no matter what I did to the settings on the Apexi nothing would change on my Zeitronix readings. The CEL was for a MAF fault and I verified that the wiring for the MAF relocation was correct and the wiring installation for the Apexi was correct for the wiring directions supplied.
I have since gone away from the Apexi and went with a second hand SMT6 and have been attempting to tune a map myself. It is close but still not perfect, but much better than before. It just needs a little more tuning.
Also, any ideas what actually causes the ECU to run in limp mode - ie. what signal actually causes the ECU to run in limp mode? If the MAF is calibrated to the AFM voltages, the ECU shouldn't be able to tell the difference.
944, 968, conversion, fuel, ls, maf, mapping, porsche, s2, s2s, sfr, supecharger, supercharged, supercharger
