Powerfc Tuning

[justin911]

yeah i followed your steps in the FAQ, not sure about fuel eco yet.. but its definetly more responsive now

[Guilt-Toy]

I had mine running at 16.5:1 on cruise and used to get 10 litres per hundred km on the freeway and had 230rwkw with a 3 litre bottom end.

[benl1981]

PaulR33 - are you getting better economy than with stock computer? I'm getting my PFC tuned on Saturday, I used to get about 10L/100 on the highway but last week I got about 12L/100kms on stock computer.

Commodore 3.8L's autos can do 10L/100km, my 2.5 Turbo manual I thought would be able to better this as I wasn't driving hard at all!

When I get the tune done I'll check cruise AFR - they should be 14.7 due to 02 sensor - I was suprised in one of your threads to see you mentioned 12.5 at cruise? You should be in closed loop then...

I was thinking due to me not being hard on the throttle much iwould have probably been in closed loop for most of the highway driving so I dont see how PFC will help much...maybe a bit more timing at low loads..??

Edited October 3, 2005 by benl1981

[justin911]

i was playing with the ol pfc again just now.. i noticed on idle the timing is at like 15 or 16.. and the water temp was 61 degrees.. In my ign maps though theres no referance to any 15's or 16's though.. There is on the stock maps though.

Where would it be getting this 15 or 16 from ? or what setting would be kicking it telling it to do somethng else ?

[Cubes]

Justin, thats another setting that the pfc h/c or datalogit cannot access. Idle ignition.

Apparently the value can't be read, only written.

The RB25 and RB20 default idle ignition value is 15degree's.

The PFC also stabilises ignition timing by the use of the stepper motor and by rocking ignition timing.

Edited October 9, 2005 by Cubes

[justin911]

cool thanks

[justin911]

hey ppls

got another quick question... the settings in the AFM section in the pfc... its got values like..

2v = 100% or woteva... if i changed that from say like 100% to 105%.. what affect would it probably have ?

From my understanding that function kinda operates like a safc... ?

also.. i shouldnt be touching this.. but under IGN/INJ if i turned the fuel down say like 5 button presses.. should i be able to tell a differance ?

like maybe the car wouldnt accerlerate as fast or something??? Im just trying to play with the fuel ever so slightly without breaking anything

thanks

[benl1981]

So does anyone know what the values in the INJ MAP mean. Are they referenced to a base map and a percentage of the base map setting? e.g. some are 1.01 and as you go down the vertical axis they usually become higher e.g 1.40

Edited January 23, 2008 by benl1981

[paulr33]

hey ppls

got another quick question... the settings in the AFM section in the pfc... its got values like..

2v = 100% or woteva... if i changed that from say like 100% to 105%.. what affect would it probably have ?

From my understanding that function kinda operates like a safc... ?

also.. i shouldnt be touching this.. but under IGN/INJ if i turned the fuel down say like 5 button presses.. should i be able to tell a differance ?

like maybe the car wouldnt accerlerate as fast or something??? Im just trying to play with the fuel ever so slightly without breaking anything

thanks

the settings on the AFM page are correction values for each voltage range.

so if you edit the number next to 2.0v and change it from %100 to %110 it means that when the load calc is used to work out where to place the load axis it applies %110 correction to the final number. so say the AFM reads 2.3v and you have %110 correction set at 2.0v then it will work out the load axis

using that scale and it will reach an abritrary "load" number which comes out of the ramp talbe (hidden in datalogit/fc pro). then it will apply %110 correction.

basically in simple terms it allows you to move the load axis up and down on the map

say if you run 15psi on xyz turbo and on full load you come out on row 18 and you decide its too low

when you do this run you find the afm is around 4.6v so on the AFM ramp table you can find the highest settings below 4.6v and edit it

so lets say on the AFM ramp screen you see 4.4v and 5.0v (these arent right but anyhoo) so you edit 4.4v to be %90 instead of %100

this means any AFM voltage above 4.4 and below 5.0v gets %90 correction instead of %100

so the final load calc runs and plots you on row 18 (as we see from map tracer) but then it applies the correction of %90 (instead of %100)

and this makes it shift the value down in load, so less load, means lower on the load axis, which means it may end up around say load point 16 instead of 18

so it allows you to bend the load axis around in summary

[paulr33]

So does anyone know what the values in the INJ MAP mean. Are they referenced to a base map and a percentage of the base map setting? e.g. some are 1.01 and as you go down the vertical axis they usually become higher e.g 1.40

hi ben,

have a read of

http://paulr33.skylinesaustralia.com/docs/...erfc-faq.htm#60

from what ive seen

around 0.94x on std injectors and no correction is around 16 AFR on R33 GTST

[paulr33]

also.. i shouldnt be touching this.. but under IGN/INJ if i turned the fuel down say like 5 button presses.. should i be able to tell a differance ?

like maybe the car wouldnt accerlerate as fast or something??? Im just trying to play with the fuel ever so slightly without breaking anything

thanks

if you press RIGHT on the IGN/INJ correction screen then you are in the INJ correction screen/mode

the Kij amount should show you latency of the injectors , which in turn will control fuel injection amount

if you press DOWN youll reduce the INJ value from the base map which will lean it out

if you want to richen it up you need to press UP to increase the correction map

as you change the number the Kij is the current map value and Fin is the final corrected amount

i would be very careful doing this without a wideband sensor cos you could be leaning it out too much

a few button presses say 5 wont do much - the difference between say 14.7 AFR and 16 AFR on stock GTST injectors/turbo etc is 1.00 down to 0.945

so its a quite a large linear scale - (ie: its not sharp and narrow). you won't notice 5 button presses either way.

[Guilt-Toy]

its funny looking at your old posts from good ol 2005, i learnt alot in that year.