LS2/LS7 coils and DWELL Time

[omnigear]

for some reason I cannot see the image >_<
is the link below the setting i need to put in the dwell duty tables?
for a rb26dett
viewtopic.php?p=20138#p20138

Not sure what you are trying to achieve doing that.... you need to raise the dwell time if you want longer pulses

See what I did with my R34 to get about from 2.5-3ms to about 5-6ms (this is from memory so watch the gauge... don't use my example verbatim)

[Matt]

You need to adjust the duty vs voltage tables and watch the 'dwell time' parameter in consult (added more common used model vehicle ECUs)

Effectively add an extra 1.5 - 2x values in this table to increase dwell time to what you need for those coils

[omnigear]

so to start just add 1.5x through out the whole table and adjust accordingly after logging, correct?

You need to adjust the duty vs voltage tables and watch the 'dwell time' parameter in consult (added more common used model vehicle ECUs)

Effectively add an extra 1.5 - 2x values in this table to increase dwell time to what you need for those coils

The 1.5x Table
22.5 22.5 33 48 63 78 90 105 120 135 150 165 175.5 190.5 207 222 237 252 267 282 297 312 327 342 349.5 349.5 349.5 349.5 349.5 349.5 334.5 334.5

OEM Table
15 15 22 32 42 52 60 70 80 90 100 110 117 127 138 148 158 168 178 188 198 208 218 228 233 233 233 233 233 233 233 233



Edit: it seems that 255 is the max. :p

[Matt]

Wrong table... that is duty vs RPM.

You want to increase the dwell time (duty vs volts)

[omnigear]

thank you, gonna try this and go from it.

[bachig24u]

STATUS post your quick tweaks so Bgytm can get on with troubleshooting the real issue.

I would like to know too so I can correctly setup the dwell time when I install my LS2 D514A coils

Hi,
Did anyone get a reply from STATUS on this?
rick88ss or Bgtym?

Bgtym,
Did you end up sorting out the misfire issue?
I had an R32 RB25DET a few weeks ago that would fire up after a LS1 coil swap. short story was, during cranking it dropped 12V feed to injectors.
Bypassing coil and injector power feed was solution. stock dwell maps work well so far.
Turbo timer was also causing idle to change when it was active, battery body earth was loose.

[omnigear]

I am getting a DTC 21 and I cannot command idle , it sticks at 1.2k instead of 950. I have checked vac leaks and nothing comes up.

[bachig24u]

omnigear, I will be checking an RB25 that had a LS1 coil swap this week. also has DTC 21.
I'll check if the idle issue is related to DTC 21.

[omnigear]

idk , i cannot even commad the idle above 1.2k or lower on nistune even if I change it.
i have the dwell back to stock and it still the same symptoms.

omnigear, I will be checking an RB25 that had a LS1 coil swap this week. also has DTC 21.
I'll check if the idle issue is related to DTC 21.

[Matt]

DTC21 is a feedback issue from the coils (since they differ to factory). You will not be able to remove the fault code itself due to the electrical characteristic differences. However the raised fault code should not affect the operation of the ECU otherwise

[bachig24u]

So far,
Vehicles using LS1 coils seem to throw up a DTC 21. no idle issue noted.

I haven't seen the issue with the LS7 coils.

04U60 and 11U00, not sure if its ECU related.

[STATUS]

By Manipulating those two dwell tables (dwell time and dwell duty) you will be able to set the correct dwell.

Ignore ignition 21 (or disable in DTC tables) it will have no effect on anything.

this is a car we had endless dramas with oem and splitfires, with new coils and 33 psi we had zero missfires by adjusting the above 2 tables. Best plugs we found were BKR8eix as we were able to get a few more psi than properly prepped coppers.

https://www.facebook.com/ChequeredTunin ... 9651649632

[omnigear]

got it sorted out, had vacuum problems .

DTC21 is a feedback issue from the coils (since they differ to factory). You will not be able to remove the fault code itself due to the electrical characteristic differences. However the raised fault code should not affect the operation of the ECU otherwise

[jjtxaz24]

sorry to bump an old thread. Im getting around to installing the LQ9 coils on an RB26 but before I did so I wanted to make sure that I understood the Dwell settings to prevent from blowing up my engine.

I read through the Nistune Mapping guide found here : http://nistune.com/docs/Nistune%20MAF%2 ... 0Notes.pdf

In there it states that the " Default Nissan coil charge time is approximately 3ms" with that said. The LS Coils from all that I've read need to be around 3.4ms. Do I still need to change the dwell time for that out even though the stock ones run at 3ms? If so the only table that I have/should need to adjust is the Dwell Time Table as Correct? Im assuming that all values in these tables are the same for all RB26 running these coils right? Can I just use someone else's values and input them into mine?

Here is a snapshot of what I'm referring too.

Dwell Time.jpg

(126.92 KiB) Downloaded 2125 times

[Matt]

Yes just the dwell time table. There is only a 13% difference from what you have there. I would start with stock and then increase the top half further if you get ignition cuts occurring. Also watch the dwell time estimate gauge in the software (if available for your vehicle)