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I have power Fc's in both my GTRs and would like to know if anyone has est if the knock sensors actually work ?

Mine is set at standard and I have never seen the light flash although I Know when we had it on the dyno it pinged during tuning because I was listening (but not watching engine light at the time) we ironed things out of course so no knock while on dyno but i just want peice of mind to know the thing will flash if theres any detonation.

Also I have a data logit but not a hand controller- how can I tell things like what my max RPM, max knock level, max other stuff has been ???

Jeremy

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OK! Dunno how much I can help, because I don't have the data logic, but the HC shows what you want under the "Monitor" setting. Apexi say in their manual, the Engine Light will flash when the PowerFC hits a Knock Level of 60.. however "Apexi" also say that this is not necessarly knock, because I do know they can pick up other sounds. Generally after my most recent tune I see knock figures between 30-40 under full load.

tonygtst is right, they are only a microphone that generate a electrical pulse under vibration.

The OEM ecu's use filters to filter out noise that will be picked up by knock sensors. Knock sensors will pick up noise and generate voltages from shockwaves that come from anywhere in the engine, vlave train, piston slap, road noise and so on. The filter in the OEM ecu's filter out the noise, and only react to the frequency that would be generated by the particular engine with detonation. It mostly comes down to bore diameter, but it is a wide frequency range. The problem with after market ECU's is that they do not descriminate, the noise from the valve ttrain may be enough to retard timing.

Well the thing about the PowerFC is that you don't need to worry about it retarding the timing unnecessarily because it doesn't. It doesn't react in any way to input from the knock sensors, it just feeds the information back to the driver to do something with.

Guest INASNT

On a warm day if i am fang mine at about 20psi i get the check engine light flash at the top of 3rd, and it registers a knock reading on the pfc hand controller of 60's all the time.

Once or twice i have checked the peaks after normal driving and seen 85 knock on the pfc but no engine check light while driving, so it sometimes picks up crap.

  • 3 weeks later...

Jezzrr,

***Edit: Just realised you don't have H/Cs in your cars... OOPS***

When your H/C is in monitor mode, pressing the up or down arrow (cant remember which) will show peak figures for all values shown. pressing the opposite one takes the peak away. Pressing the right arrow when the peak value is showing will reset the peak to 0 and starts again. Pressing the left arrow freezes the current reading on the screen so you don't have to have the peak showing....

Also did you know that if you press 'next' when in monitor mode you get a cool line graph for whatever values you have set in the monitor mode? IE if you are monitoring 4 things, you get a line graph with 4 lines doing their own thing. Boost is good to use this with as you can see how well it holds peak boost and pick up any spikes etc...

Hope this helps

Brett

Jeremy... Buy *ONE* hand controller - buy *TWO* PS2 IBM PC keyboard extension cables.

Cut the relevant pins - installed into both your GT-R's. Have the cable curl around the passenger seat.

Just bring the HC with you depending on which GT-R you feel like driving (must be a tough decision you have there - I feel for ya).

It'll give you a better feel for what the car is doing.

Also engine damage can occur with the engine check light not lit.

T.

in datalogit you go to monitor mode and you can view live readings like knock and all other engine functions just like the hand controller.. but better as you can logit and view knock readings after you have done a dyno run or race to see how the tune is and were it needs adjustments...

cheers...hope this helps...

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