VE range on 7747
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VE range on 7747
What is the numerical range for the main VE table? Logically it seems like they shouldn't go over 100, but I'm getting very close to that as I tune. I'm wondering if I should scale the whole table down and adjust up BPW or VE adder table or something? Does the VE adder literally just add its number to the whole RPM row on the main VE?
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Re: VE range on 7747
What is the numerical range for the main VE table? Logically it seems like they shouldn't go over 100, but I'm getting very close to that as I tune. I'm wondering if I should scale the whole table down and adjust up BPW or VE adder table or something? Does the VE adder literally just add its number to the whole RPM row on the main VE?
RBob.
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Re: VE range on 7747
https://www.thirdgen.org/forums/diy-...yyyy-down.html
I have been wondering why VE Main and Adder add up to over 100? Over tha last 5 years I have found 4-5 XDF for $42 and combined them all, they were all the same as Mastiff pictured? Has this been wrong forever?
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Re: VE range on 7747
From the ASDX $42 hac
And the adder:
Code:
;---------------------------------------------
; MAIN FUEL (VE1) Vs. MAP Vs. RPM
;
; 10-05-2000 Dissassemby of ASDX
; 8 COL x 9 BLOCKS = 72 BYTES
;
; TBL = 2.56 * VE %
;---------------------------------------------
ORG $037C ;
L037C FCB 0 ; MIN RPM Val
L037D FCB 16 ; Min KPA MAP Val
L037E FCB 8 ; LINES/BLOCK
;---------------------------------------------
; 20 KPA MAP
; VE % RPM
;---------------------------------------------
L037F FCB 5 ; 2.0 400
L0380 FCB 10 ; 3.9 800
L0381 FCB 15 ; 5.9 1200
L0382 FCB 25 ; 9.8 1600
L0383 FCB 36 ; 14.1 2000
L0384 FCB 46 ; 18.0 2400
L0385 FCB 66 ; 25.8 2800
L0386 FCB 75 ; 29.3 3200
;---------------------------------------------
; 30 KPA MAP
; VE % RPM
;---------------------------------------------
L0387 FCB 36 ; 14.1 400
L0388 FCB 63 ; 24.6 800
L0389 FCB 79 ; 30.9 1200
L038A FCB 96 ; 37.5 1600
L038B FCB 107 ; 41.8 2000
L038C FCB 109 ; 42.6 2400
L038D FCB 106 ; 41.4 2800
L038E FCB 90 ; 35.2 3200
;---------------------------------------------
; 40 KPA MAP
; VE % RPM
;---------------------------------------------
L038F FCB 36 ; 14.1 400
L0390 FCB 64 ; 25.0 800
L0391 FCB 90 ; 35.2 1200
L0392 FCB 103 ; 40.2 1600
L0393 FCB 112 ; 43.8 2000
L0394 FCB 114 ; 44.5 2400
L0395 FCB 118 ; 46.1 2800
L0396 FCB 116 ; 45.3 3200
;---------------------------------------------
; 50 KPA MAP
; VE % RPM
;---------------------------------------------
L0397 FCB 45 ; 17.6 400
L0398 FCB 65 ; 25.4 800
L0399 FCB 97 ; 37.9 1200
L039A FCB 109 ; 42.6 1600
L039B FCB 117 ; 45.7 2000
L039C FCB 122 ; 47.7 2400
L039D FCB 125 ; 48.8 2800
L039E FCB 127 ; 49.6 3200
;---------------------------------------------
; 60 KPA MAP
; VE % RPM
;---------------------------------------------
L039F FCB 79 ; 30.9 400
L03A0 FCB 92 ; 35.9 800
L03A1 FCB 105 ; 41.0 1200
L03A2 FCB 116 ; 45.3 1600
L03A3 FCB 124 ; 48.4 2000
L03A4 FCB 127 ; 49.6 2400
L03A5 FCB 135 ; 52.7 2800
L03A6 FCB 137 ; 53.5 3200
;---------------------------------------------
; 70 KPA MAP
; VE % RPM
;---------------------------------------------
L03A7 FCB 97 ; 37.9 400
L03A8 FCB 100 ; 39.1 800
L03A9 FCB 108 ; 42.2 1200
L03AA FCB 120 ; 46.9 1600
L03AB FCB 126 ; 49.2 2000
L03AC FCB 136 ; 53.1 2400
L03AD FCB 140 ; 54.7 2800
L03AE FCB 137 ; 53.5 3200
;---------------------------------------------
; 80 KPA MAP
; VE % RPM
;---------------------------------------------
L03AF FCB 103 ; 40.2 400
L03B0 FCB 106 ; 41.4 800
L03B1 FCB 113 ; 44.1 1200
L03B2 FCB 123 ; 48.0 1600
L03B3 FCB 131 ; 51.2 2000
L03B4 FCB 135 ; 52.7 2400
L03B5 FCB 140 ; 54.7 2800
L03B6 FCB 141 ; 55.1 3200
;---------------------------------------------
; 90 KPA MAP
; VE % RPM
;---------------------------------------------
L03B7 FCB 110 ; 43.0 400
L03B8 FCB 115 ; 44.9 800
L03B9 FCB 122 ; 47.7 1200
L03BA FCB 125 ; 48.8 1600
L03BB FCB 133 ; 52.0 2000
L03BC FCB 143 ; 55.9 2400
L03BD FCB 144 ; 56.3 2800
L03BE FCB 152 ; 59.4 3200
;---------------------------------------------
; 100 KPA MAP
; VE % RPM
;---------------------------------------------
L03BF FCB 120 ; 46.9 400
L03C0 FCB 120 ; 46.9 800
L03C1 FCB 124 ; 48.4 1200
L03C2 FCB 127 ; 49.6 1600
L03C3 FCB 128 ; 50.0 2000
L03C4 FCB 148 ; 57.8 2400
L03C5 FCB 159 ; 62.1 2800
L03C6 FCB 160 ; 62.5 3200 Code:
; MAIN FUEL TBL vs RPM, FL2
;
; 01-31-2000 Dissassemby of asdx
; 17 BYTES
;
; TBL = 2.56 * VE %
;---------------------------------------------
ORG $03C7 ; VE % RPM
;---------------------------------
L03C7 FCB 64 ; 25.0 0
L03C8 FCB 100 ; 39.1 400
L03C9 FCB 100 ; 39.1 800
L03CA FCB 100 ; 39.1 1200
L03CB FCB 100 ; 39.1 1600
L03CC FCB 100 ; 39.1 2000
L03CD FCB 100 ; 39.1 2400
L03CE FCB 100 ; 39.1 2800
L03CF FCB 100 ; 39.1 3200
L03D0 FCB 105 ; 41.0 3600
L03D1 FCB 90 ; 35.2 4000
L03D2 FCB 82 ; 32.0 4400
L03D3 FCB 55 ; 21.5 4800
L03D4 FCB 45 ; 17.6 5200
L03D5 FCB 25 ; 9.8 5600
L03D6 FCB 0 ; 0.0 6000
L03D7 FCB 0 ; 0.0 6400 
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Re: VE range on 7747
i remember reading one of RBob's tuning articles and, for whatever reason, the main VE table + adder equaled more than 100. it has something to do with the calc's maybe? in my situation i just keeping adding and when the PW doesnt increase anymore i know ive reached the PW limit lol.
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Re: VE range on 7747
i remember reading one of RBob's tuning articles and, for whatever reason, the main VE table + adder equaled more than 100. it has something to do with the calc's maybe? in my situation i just keeping adding and when the PW doesnt increase anymore i know ive reached the PW limit lol.
Also, I've been following the advice of pulling the VE2 table into VE1 for easier tuning. In that case on ARJT some cells are already over 100 and tunerpro truncates them to 100 right in the table.
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Re: VE range on 7747
I've tuned many 7747 as is. Some guys say to add adder table to main VE and work off it. That is when I found a stock chip is already over 100. So I left it be and just tuned main VE. Once I get to 95 I raise fuel pressure and start over... now I use an Injector Calculater which uses injector size engine approx HP and calculated fuel pressure. This way I know I have enough fuel top end, then tune...
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Re: VE range on 7747
I've tuned many 7747 as is. Some guys say to add adder table to main VE and work off it. That is when I found a stock chip is already over 100. So I left it be and just tuned main VE. Once I get to 95 I raise fuel pressure and start over... now I use an Injector Calculater which uses injector size engine approx HP and calculated fuel pressure. This way I know I have enough fuel top end, then tune...
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Re: VE range on 7747
Since then it has been a never ending battle, even many of the '8746 ECU files are the same way, maybe copied my '7747 ECU updates? If it is missing a MAP row, then they were copied, as I also goofed that up.
As for the VE1 and VE2 adding up to more then 100%, yup, even the GM tuners got caught on that one. The ECM will note this and set it to 100% to prevent overflow to a lower number.
The two VE tables are a PITA, which is the first thing I was rid of when I started to re-write the ECM firmware (also went to larger and higher resolution tables).
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Re: VE range on 7747
I don't know Bob? I just copied the VE Main and set it up RPM columns and MAP rows and it does not read the bin file correctly? Unless something else is wrong? The origanal way is reading from the $42 HAC of ASDX correctly but not if I switch rows and columns?
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Re: VE range on 7747
Code:
LDX #$D032 ; MAIN SA TABLE ; LDAB L0026 ; S/D MAP LDAA L001B ; rpm / 12.5 & 25, brk @ 2400, start 400 rpm, limited to 3600 ; JSR LFB67 ; 3d LK UP
Then the VE1 look up:
Code:
LDAA L0026 ; S/D MAP LSRA ; DIV BY 2 FOR LK UP LDAB L001C ; RPM/25 CMPB #128 ; 3200 RPM BLS LD6BD ; BR IF RPM LT 3200 ; LDAB #128 ; FORCE 3200 RPM LD6BD: LDX #$D37C ; POINT TO FL 1 TABLE JSR LFB67 ; 3D LOOK UP
RBob.
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Re: VE range on 7747
RBob, you know I take your word as a mentor! And well that explains it, but why does it not work?
I ran a log file and data tracing with both VE Main and VE Main Corrected, changed row and column axis and the corrected one stayed at 100 MAP 400 RPM while the original worked fine...
So is just changing the table to correct not enough. It reads the bin wrong and data traces wrong. While the one that is built wrong (original) works right?
EDIT: Since they got VE Main and VE Adder over 100 as a mistake could this be a mistake too?
EDIT: Removed wrong xdf, correct XDF is below.
I ran a log file and data tracing with both VE Main and VE Main Corrected, changed row and column axis and the corrected one stayed at 100 MAP 400 RPM while the original worked fine...
So is just changing the table to correct not enough. It reads the bin wrong and data traces wrong. While the one that is built wrong (original) works right?
EDIT: Since they got VE Main and VE Adder over 100 as a mistake could this be a mistake too?
EDIT: Removed wrong xdf, correct XDF is below.
Last edited by EagleMark; Mar 16, 2012 at 09:24 AM.
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Re: VE range on 7747
RBob, you know I take your word as a mentor! And well that explains it, but why does it not work?
I ran a log file and data tracing with both VE Main and VE Main Corrected, changed row and column axis and the corrected one stayed at 100 MAP 400 RPM while the original worked fine...
So is just changing the table to correct not enough. It reads the bin wrong and data traces wrong. While the one that is built wrong (original) works right?
EDIT: Since they got VE Main and VE Adder over 100 as a mistake could this be a mistake too?
I ran a log file and data tracing with both VE Main and VE Main Corrected, changed row and column axis and the corrected one stayed at 100 MAP 400 RPM while the original worked fine...
So is just changing the table to correct not enough. It reads the bin wrong and data traces wrong. While the one that is built wrong (original) works right?
EDIT: Since they got VE Main and VE Adder over 100 as a mistake could this be a mistake too?
Change the new 'VE as % (FL1) Corrected' entry to row centric and it is correct.
Not sure why that entry parameter would be used, as it adds another level of complexity and confusion. See the Major Order parameter in the pic.
RBob.
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Re: VE range on 7747
Well that did it! 
VE from HAC are in place, data tracing is working correctly!
But since you compared it to spark above I looked at my Main Spark advance and it is set to row? But data tracing seems to work fine either way if I set columns or rows? Sure changes where the spark numbers are though? Main Spark has always been MAP kpa acorss top and RPM down left side, like new corrected Main VE table... but set to row?
VE from HAC are in place, data tracing is working correctly!
But since you compared it to spark above I looked at my Main Spark advance and it is set to row? But data tracing seems to work fine either way if I set columns or rows? Sure changes where the spark numbers are though? Main Spark has always been MAP kpa acorss top and RPM down left side, like new corrected Main VE table... but set to row?
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Re: VE range on 7747
JK...
The Main VE is fixed thanks to RBob, I checked the spark table and it lines up with $42 HAC. I was just asking if it needed a corection as well.
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Re: VE range on 7747
Can also do it the latest way EagleMark did, by going back to the default settings and changing the row/column annunciation. Which will show the rows & columns swapped.
My preference would be to use the method that follows how GM did the table layout. Which is using the row centric layout and with the MAP as rows and RPM as columns.
Note that this is for the VE1 table, no others.
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Re: VE range on 7747
HI RBOB.JUST A QUESTION .IF 747 VE TABLE GOES 6400 RPMS,WHY IS 730 SO POPULAR?OR IS IT JUST A BAUD THING.ARE THERE OTHER ECMS THAT GO HIGHER AND COMPAT. WITH 91 STYLE IGNITION & FUEL SYSTEMS?
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Re: VE range on 7747
The '7730 ECM in stock form is for MPFI set ups (like TPI), or a single 1-bbl TBI (on 4-bangers).
The '7730 is stock in '90-'92 f-body TPI set ups and the 3.1l MPFI set ups.
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