PDA

View Full Version : firing order change.


AllOutPerformance
August 24th, 2014, 10:56 AM
Can i change the firing order in the pcm rather then re pinning stuff.What i have is a 500 inch bbc with a 4 7 swapped camshaft and id really like to just change the firing order in the tune..Thanks
joecar
August 24th, 2014, 08:01 PM
No... re-pining/re-routing only.
AllOutPerformance
August 24th, 2014, 08:12 PM
No... re-pining/re-routing only.

Tunercats will do it.kinda a bummer efi live doesnt allow it...I repinned it and got it fired up tonite...thanks for the reply joe
GMPX
August 24th, 2014, 11:54 PM
I don't think it works like that, the PCM only knows A-H outputs, the wiring team at GM route the wires to the correct injectors/ign coils.
MICK
August 25th, 2014, 01:51 AM
Cough,,LOL never say never
Taz
August 25th, 2014, 02:05 AM
... Tunercats will do it.kinda a bummer efi live doesnt allow it...

Interesting ... with HPT the Gen III firing order is part of the engine diagnostics parameters. I have never changed this, but my assumption was that altering this table was for the purpose of updating the misfire detection algorithm, after repinning the PCM to mechanically change the firing order, as you have done.

I still learn something everyday ...
AllOutPerformance
August 25th, 2014, 07:14 AM
Watch "Bbc with gm ls1 ecu first fire up" on YouTube
Bbc with gm ls1 ecu first fire up: http://youtu.be/qTuVPed3HR0
joecar
August 25th, 2014, 07:47 AM
Sounds and runs great, throttle response is instant :cheers:
GMPX
August 25th, 2014, 10:37 AM
Interesting ... with HPT the Gen III firing order is part of the engine diagnostics parameters. I have never changed this, but my assumption was that altering this table was for the purpose of updating the misfire detection algorithm
I am of the same opinion.