Power FC knock control and J&SS
10-19-06, 12:12 PM
#1
knock control and J&SS
I have been getting information about the PFC as I am looking into a programmable ECU. I understand that the PFC does not have any knock control loop to retard ignition, like the OE ECU.
I thought that installing a J&S Safeguard could overcome this imitation. However, I found out that the J&SS only controls the common leading coil to the leading sparks but not the two trailing coils. This is puzzling as it could get the trailing sparks firing ahead of the leading. Besides, I don’t know if retarding the leading but not the trailing would still be effective in minimizing detonation.
Is there any solution for that?
I thought that installing a J&S Safeguard could overcome this imitation. However, I found out that the J&SS only controls the common leading coil to the leading sparks but not the two trailing coils. This is puzzling as it could get the trailing sparks firing ahead of the leading. Besides, I don’t know if retarding the leading but not the trailing would still be effective in minimizing detonation.
Is there any solution for that?
10-22-06, 02:25 AM
#2
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with the PFC if its knocking you can see this via the hand controller
and you will see a CEL if it goes over a certain safe level
so its acceptable in this case (apexi also thought so)
doing brainded retard timing is probably the worst way to approach it
much better approaches to fixing it, than doing brainded back off timing and not alert the user type actions
and you will see a CEL if it goes over a certain safe level
so its acceptable in this case (apexi also thought so)
doing brainded retard timing is probably the worst way to approach it
much better approaches to fixing it, than doing brainded back off timing and not alert the user type actions
10-22-06, 12:32 PM
#3
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If you use the J&S, then you have to run more split than the max it will retard the IGL in order to prevent the IGT firing first (negative split).
I had one but finally got rid of it. The problem is with adjusting the sensitivity to work but only when the knock level is really knock and not noise. If your normal knock/noise is 20, you do not want the unit working that low.
I had one but finally got rid of it. The problem is with adjusting the sensitivity to work but only when the knock level is really knock and not noise. If your normal knock/noise is 20, you do not want the unit working that low.
10-23-06, 10:05 PM
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Originally Posted by Sandro
Do you imply the stock ECU closed-loop knock control is also worthless? I haven't checked on the shop manual but I believe it would retard both leading and trailing.
10-23-06, 10:08 PM
#7
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Originally Posted by Sandro
Is there any reason why the L and the T could not be made to fire together? (excl. emission considerations)
Basically has been/is done for NA engines. Not very feasable for turbo engines.
When doing so to a turbo engine, timing has to be really low (6 to 0 IGL).
Search this site for the big discussion threads on timing.
Trending Topics
10-23-06, 10:26 PM
#8
Interesting to hear that the stock knock control system is useless even with a stock engine...
I guess I must have been lucky.
As for the timing issue, thank you for the reference. I will be looking other applicable threads.
Is there any specific archive you could refer me to? Sorry but I haven't used/ followed the forum much in the past since I haven't done any mods yet.
I guess I must have been lucky.
As for the timing issue, thank you for the reference. I will be looking other applicable threads.
Is there any specific archive you could refer me to? Sorry but I haven't used/ followed the forum much in the past since I haven't done any mods yet.
10-23-06, 10:39 PM
#9
The day will come when everyone understands that knock retard will never stop a rotary engine from knocking or blowing up. You can turn all the spark off when a rotary is knocking and it will keep on running because rotaries suffer from pre-ignition mainly. I wil be starting a thread soon to discuss what I said above.
Last edited by crispeed; 10-23-06 at 10:41 PM.
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