I am wondering what effects changing the main spark bias would have on my main spark. If I understand the main spark bias correctly, changing the main spark bias will change the spark bias in all the cells? If I understand the main spark bias correctly, if I change the main spark bias from 20* to a new value of 10* to ECM will only be able to SUBTRACT 10 degrees? Thanks, dave w

If I understand correctly, if you change the Main Spark Bias you will need to either lower or raise the Main Spark Table by the same amount, and it will apply to all cells. The Main Spark Bias is the amount the Main Spark Table can go negative, not the amount of available spark retard.

In the Tuning Guide Book sticky, Chap 5., '8063/'8746/'7747 ECM. See the spark logic thread.

RBob.

Thanks RBob,
My ECM number is 16168625 which is the E6 definition file. I really never know at least 100% for sure information for other ECM / Definition files all work the same?
dave w

When I tried that, because the Bias (LC10A Arap) is subtracted from the Correction table (10F-17A), it only subtracted 10 Degrees not 20 degrees so all the spark advance was 10 degrees more (lots of spark knock and retard).

It is my understanding, that this allows for negative values, to be used in this table. If you have 20 degrees correction and the 20 degrees bias is subtracted, you have 20-20=0, also 20-10=10, and 10-20=-10.

It would be an easy global change to check for "how close am I to knock retard" in all areas, for those of us that run some degrees under knock.

I found some E6 HAC information at Moates.

dave w

;--------------------
; SPARK TABLE BIASES
;--------------------
L4137: FCB 28 ; 9 Deg MAIN SPK BIAS
L4138: FCB 57 ; 20 Deg COOLANT SPK BIAS
L4139: FCB 29 ; 10 Deg BIAS ALT ADV CORR BIAS
L413A: FCB 0 ; 0 Deg EGR BIAS
L413B: FCB 0 ; BIAS FOR MAP CORR SA.
;--------------------

L413C: FCB 167 ; 85 c, COLD THRES FOR NEG SPK NOT USED
;
L413D: FCB 8 ; NUM CYL'S, (4, 6 or 8)
;
L413E: FCB 6 ; 6 NUM CNT'S, SPK RUN FLAG SET IF RPM GT 6 DRP'S
L413F: FCB 2 ; 2 CNT'S FUEL RUN FLG, IF RPM G.T. 2 DRP'S
;
L4140 FDB 0119 ; 42 Deg, Max Adv
L4142: FDB 65508 ; 10 Deg, Max Retard
L4144: FDB 65508 ; 10 Deg, Max Retard DURING FUEL C/O
L4146: FDB 65508 ; 10 Deg, Max Retard DURING TORQUE MANAGMENT FUEL C/O
;
L4148: FCB 15 ; 6% COEF START UP SPK MULT COEF
L4149 FCB 10 ; 4% COEF DECEL FUEL CUT SPK MULT FILT
L414A FCB 20 ; 8% COEF DECEL FUEL CUT SPK MULT FILT

L414B FCB 25 ; 9.8% TPS DECEL FUEL CUT SPK FILT SLECT THRESH
L414C FCB 28 ; 10 Deg DECEL FUEL CUT SPK ADV
L414D FCB 240 ; 93.8% RPM FILT TIME CONST

Dave where did you find the e6 hack stuff I am workong on a ADS file and that info would be great I dont remember seeing it ont he site. The ads file up on the site does not work very well

/5) Source Code and Hacks/

or maybe this link


http://www.moates.net/fileman/index.php?dir=5)%20Source%20Code%20and%20Hacks

The user name is moatesuser and the password is moatespassword