LS2/LS7 coils and DWELL Time

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supersayianjim
 

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Re: LS2/LS7 coils and DWELL Time

Post by supersayianjim »

actually I have the ones with the heat snk on them. no external ignitor needed(like on s2 rb25)

Image
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Re: LS2/LS7 coils and DWELL Time

Post by Matt »

I would not advise altering the second table unless you want to increase/decrease the dwell time based on RPM

The second dwell/RPM table is to compensate for the ECU pulses being generated from the RPM signal. As the RPMs increase, the pusle generator in the ECU has shorter pulses. This RPM/dwell table increases the pulsewidth adjustment to keep a consistent 2.5-3ms dwell charge time to the factory coils
supersayianjim
 

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Re: LS2/LS7 coils and DWELL Time

Post by supersayianjim »

Matt wrote:I would not advise altering the second table unless you want to increase/decrease the dwell time based on RPM

The second dwell/RPM table is to compensate for the ECU pulses being generated from the RPM signal. As the RPMs increase, the pusle generator in the ECU has shorter pulses. This RPM/dwell table increases the pulsewidth adjustment to keep a consistent 2.5-3ms dwell charge time to the factory coils


I don't know what you said(iam dumb)..
Matt
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Re: LS2/LS7 coils and DWELL Time

Post by Matt »

Higher RPMs would result in a smaller dwell time if the table was flat. The table is a calibration to keep the dwell time consistent at all RPMs
scottmt21
 

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Re: LS2/LS7 coils and DWELL Time

Post by scottmt21 »

Is it normal that an ignition DTC code is thrown after installing these coils and removing the PTU on a VG30dett? How can I get it to go away? or is this just normal and I should Ignore it? Thanks
Ben C
 

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Re: LS2/LS7 coils and DWELL Time

Post by Ben C »

Yes the code is normal.

There should be an option to disable it in the dtc flag section I think (not sure on your particular ecu, there is for stagea)
Bgtym
 

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Re: LS2/LS7 coils and DWELL Time

Post by Bgtym »

use 32 ECU mec-r117. what version corrected code, dwell time at high speeds rev. will work on the EEPROM.
Torque
 

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Re: LS2/LS7 coils and DWELL Time

Post by Torque »

If you want to increase dwell time for a certain RPM range would you increase or decrease the DWELL DUTY CYCLE GRAPH?
NT_DWELL.jpg
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Matt
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Re: LS2/LS7 coils and DWELL Time

Post by Matt »

Yes you would
Bgtym
 

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Re: LS2/LS7 coils and DWELL Time

Post by Bgtym »

perform poorly coil LS2.
those as in the middle
Image
ECU set r32 installed the latest ENT (HCR32_FOR_RB25_11U0F_MT_TPS_VCT_LEDOUT_v5_FP.ent)

1)increased dwell time as in the picture above.
Image
it gave me a stable 3.4 ms all over the map! but the engine is idling is not stable and at higher loads simply cuts off the spark.
  If you press the throttle less than 1\4 (low load), the motor spins up to the cutoff, as the only full throttle there is no spark! 21 lit error (how to remove error 21?)
ignition time keeps in map. 40-23
temp 90
afr 14,7 - 12
detonation
no knock
raised the dwell time so get 5ms. no results!
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Re: LS2/LS7 coils and DWELL Time

Post by Matt »

If this is the case you may need to adjust the RPM/dwell table to reduce the time at low idle. I dont think the dwell should be that high for these coils as I'm reading based on feedback so far
Bgtym
 

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Re: LS2/LS7 coils and DWELL Time

Post by Bgtym »

Idling I increased the card RPM/dwell and it improved a little work.
at high load that does not work! all also lost spark.
Code 21 is lit why? this may be the reason?
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Re: LS2/LS7 coils and DWELL Time

Post by Matt »

You can only increase dwell so far on the ECU using that RPM table

Code 21 is when the ECU does not see the expected ignition feedback. Aftermarket coils have a different spark characteristic which can trigger this fault code.
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Re: LS2/LS7 coils and DWELL Time

Post by STATUS »

try bcpr7eix @ 0.6mm you should be able to run 30psi with those coils
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Re: LS2/LS7 coils and DWELL Time

Post by bachig24u »

I would expect a faulty coil or wiring issue.

Not having any issues with LS2 coils on standard coil maps from 04Uxx.
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