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Re: P01 '0411 12200411 v6 support
Posted: Mon Jan 21, 2019 4:43 pm
by Dylan
I've only done it once and I didn't tune it but all feedback was good. Reference signal from DFI connected to crankshaft signal input. Low res selected in the bin and 6 cylinders selected. That's what I done and sent it off. It was a good fun job that one very interesting. It was an all care no responsibility job we were all in in for learning. I have the tuned bin on file 3 bar VY V8 mafless as a base. No PCM mod's were done. All software and wiring.
No cam signal to PCM puts it back to bank firing of injectors. Cam signal to DFI still though.
Re: P01 '0411 12200411 v6 support
Posted: Mon Jan 21, 2019 4:47 pm
by Dylan
I also read online of somebody claiming to do a similar scenario on a 4 cylinder engine. But had to flag the misfire DTC's for the unused cylinders as they fitted the LS1 reluctor wheel on the front of the balancer. Take it for what it is.
Re: P01 '0411 12200411 v6 support
Posted: Mon Jan 21, 2019 5:51 pm
by antus
Ive been studying the operating system code, and there are various places where it checks the cylinder number is 8 or 6, and handles the 2 options sensibly. There is no code in there for any other number of cylinders, so I think on a 6 cyl everything would be sweet, but on a 4 cyl you'd want to select 8, and then some stuff would be 50% out which could get messy.
Code like this in 12202088, where its got a clause for 6 cyl, otherwise 8 cyl is assumed.
Code: Select all
ROM:0007797A cmpi.b #6,(Cylidners).l <--- 6 cyl?
ROM:00077982 bne.s loc_7798A <---- if its not 6 cyl jump below the line for 8 cyl
ROM:00077984
ROM:00077984 loc_77984:
ROM:00077984 clr.b ($FFFFA649).w <--- otherwise do this for 6
ROM:00077988 bra.s loc_779B8
ROM:0007798A ; ---------------------------------------------------------------------------
ROM:0007798A
ROM:0007798A loc_7798A:
ROM:0007798A tst.b ($FFFFA649).w <---- 8 cyl
ROM:0007798E bne.s loc_779A0
ROM:00077990 cmp.w (off_8020+2).l,d3
ROM:00077996 bcs.s loc_779B8
ROM:00077998 move.b #1,($FFFFA649).w
Re: P01 '0411 12200411 v6 support
Posted: Mon Jan 21, 2019 6:00 pm
by Dylan
That makes sense as 6 is a factory option for a single coil output
Re: P01 '0411 12200411 v6 support
Posted: Tue Jan 22, 2019 12:08 pm
by Holden202T
geez your digging right in there Antus!
Re: P01 '0411 12200411 v6 support
Posted: Tue Jan 22, 2019 6:51 pm
by delcowizzid
Dylan was there wiring back to the dfi or was it just runni g 10 degree base time and no eco control
Re: P01 '0411 12200411 v6 support
Posted: Tue Jan 22, 2019 6:56 pm
by Dylan
Grounded the EST wire so PCM was always in control of spark advance. Then spark trigger from PCM to DFI.
Just to be clear I only done it the once. Car was interstate and I didn't tune it.
Re: P01 '0411 12200411 v6 support
Posted: Tue Jan 22, 2019 8:22 pm
by antus
Makes sense.. pcm doesnt know engine angle of rotation. Batch fires, sends spark pulses out cyl 1. DFI knows which coil and routes it the right way. PCM handles crank spark.
Re: P01 '0411 12200411 v6 support
Posted: Tue Jan 22, 2019 8:29 pm
by Dylan
Pretty much. Reports were positive. I have the bin file I would be happy to share it with Antus.
Re: P01 '0411 12200411 v6 support
Posted: Tue Jan 22, 2019 9:07 pm
by antus
I reckon low res crank option, 6 cyl setting, wire it like you say. Simple as that. More cost, less features than 11p on a 424. Newer pcm. More after market tuners. Pros and cons.