False knock or not?

FlashPro questions & answers specific to the 2006-2009 (US, UK, Asia) S2000
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krando
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Joined: Sun Jul 17, 2016 1:22 am

False knock or not?

Post by krando » Mon May 28, 2018 1:04 am

Hi,
My datalogs show knock counts at low cam with stock calibration. To understand if it is false knock or not, I reduced the ignition timing by 2 degrees at ignition low table. I have got again knock counts mostly between 2500-4000 rpm and %20-%30 throttle.
My car specs:
Model year 2009 Euro spec DBW with 30.000 kilometers on odometer.
Briancrower stage 2 cams
Aem v2 CAI
Straight pipe custom exhaust with testpipe
Eibach sway bars (front+rear)
Engine torque damper
Diff mount collars

The calibration with reduced timing and datalog is attached

I will appreciate if you help me to understand if this is false knock or not.
Attachments
fz_s2000_239whp_v6deneme.fpcal
(8.43 KiB) Downloaded 58 times
xxx.fpdl
(122.51 KiB) Downloaded 58 times

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Hondata
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Re: False knock or not?

Post by Hondata » Mon May 28, 2018 6:41 am

It is not real knock. Probably from the cams, exhaust or engine mount. Seems to be from a resonance at 3600 rpm.
Hondata

krando
Posts: 8
Joined: Sun Jul 17, 2016 1:22 am

Re: False knock or not?

Post by krando » Mon May 28, 2018 7:23 am

Thank you very much for your answer.
Than I will load back the stock low cam ignition table and leave it that way. For the knock sensitivy low table what value should I set? It looks like 100 will be enough or should I go up to 204 like the first 3 columns

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Hondata
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Re: False knock or not?

Post by Hondata » Mon May 28, 2018 9:59 am

The real issue is the increased mechanical noise from the engine. Increase the knock sensitivity tables where you see the knock control increasing until the knock control stays around 60%. The problem I see is that you are getting knock readings at low load and 3600 rpm, where the knock sensitivity is already at the maximum.
Hondata

shind3
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Location: Pittsburgh, PA

Re: False knock or not?

Post by shind3 » Wed May 30, 2018 4:55 pm

Hondata wrote:
Mon May 28, 2018 9:59 am
The real issue is the increased mechanical noise from the engine. Increase the knock sensitivity tables where you see the knock control increasing until the knock control stays around 60%. The problem I see is that you are getting knock readings at low load and 3600 rpm, where the knock sensitivity is already at the maximum.
I'm inferring here but does increasing the Knock Sensitivity values for a given cell reduce a detected knock's effect on the global Knock Control value?

The Flashpro help says this.
The knock sensitivity tables set the amount of noise from the knock sensor which the ECU will accept before it determines that the engine is knocking. A low value will increase the sensitivity to knock sensor noise.
But changing this table seems to have no effect on Knock Count.

shind3
Posts: 111
Joined: Mon Jun 30, 2014 8:02 am
Location: Pittsburgh, PA

Re: False knock or not?

Post by shind3 » Tue Jul 03, 2018 9:48 pm

To confirm, 'Knock Sensitivity' has no effect on the calculation of Knock Control or Knock Counts. The help file is wrong. There are no currently defined tables that govern how to tune what the ECU thinks is Knock.

'Knock Sensitivity' may modify the multiplication of 'Knock Control' and 'Knock Retard'.

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