"OEM detects knock at 1200rpm+, J&S is 1750rpm+"
The J&S is in addition to the OEM system, it does not dis-able the OEM system
The OEM system software has the Knock sensor dis-abled above 3200 RPM, this works as a bad fuel sensor at low RPM, but is ineffective in the area needed for a modified turbocharged system. The engine is most sensitive to knock at peak torque and higher RPM’s in a turbocharged system running higher than stock boost levels with a boost controller. Peak torque on most Z32 set ups is between 4500 to 5500 RPM."OEM has per-cylinder knock-thresholds, J&S uses the same sensitivity for all cylinders." Again J&S is used in addition to the stock system
The Stock system is only making changes if it detects knock below 3200RPM.
The J&S makes changes for knock through the whole area that makes boost, where it is needed. J&S has an extremely fast modern processor that only requires setting the sensitivety for knock on the engine it is used on. It can be set to pull timing on individual cyl's, or all cyl’s. You can also set how much timing you want to pull. "OEM knock detection can be turned on/off for individual ignition map cells, J&S can't" Not sure why you would not want knock detection all the way through the boosted power band. The OEM system does nothing if it see’s knock at peak torque and above. "OEM uses knock to switch between high/low octane maps, J&S nope" Again the J&S is in addition to the OEM system, the J&S is a knock controller to retard timing if the stock system does not do it’s job and knock is detected. Again the stock system does not work at peak torque and above where you need it most! "OEM allows custom tuning different knock retard/advance limits for different areas of the ignition map, J&S doesn't" The J&S is always monitoring knock, it does not require setting differently in different areas because it has a very fast processor and easily detects knock from other engine noise. The OEM turns off when you need it most, if you want knock protection in boost, you either need an additional system like the J&S, or a modern day stand alone ECU. "OEM lets you to monitor all of the parameters in real-time over the consult port, J&S has no software interface." J&S is a additional system with it’s own modern processor and software. The J&S monitors knock and displays real time on the units LED’s, or on a optional gauge. "And contrary to popular belief, the OEM system does actually do knock control all the way to redline!" Sounds like a stretch…..
The OEM will use the knock map to redline, but will not enter into the knock map when needed at peak torque and above, so it is truly useless for a modified Z32 in the area the engines have the ability to produce the most knock, under boost.
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