a MAF too small

[Knowlden and/or Eller]

Here is a cut of the 7165 vette hac:


******************************************************
* Mass Air Flow Tables & Param's
*
* DIGITAL MASS FLOW SENSOR
*
* Freq range 34 - 150 hZ
* Period 927 - 437 counts
* Range 1490 counts
*
* table 1 0 - 511 counts, 0 - 22 gms/sec
* table 2 512 - 767 counts, 22 - 48
* table 3 768 - 1023 counts, 48 - 82
* table 4 1024 - 1279 counts, 82 - 135
* table 5 1280 - 1535 counts, 135 - 206
* table 6 1536 - 1791 counts, 206 - 255
*
*
*******************************************************
ORG $069A
LC69A: FCB 80 ; Ld VAR FOR SCALING LV8 SCALE FACTORS
; CAL = arg + 64, (16)
LC69B: FCB 10 ; 1 Sec MAF BURN OFF TIME.
LC69C: FCB 50 ; 5 SEC MAF BURNOFF DELAY TIME FROM IGN OFF
ORG $069D
;----------------------------------------
; Mass Air Flow TABLE 1
;
; TBL = gms/Sec * 11.1
;
;----------------------------------------
LC69D: FCB 23 ; TABLE SCALAR
LC69E: FCB 8 ; 9 LINE TBL
;----------------------------------------
; gms/SeC BIN VDC #/HR
;----------------------------------------
FCB 0 ; 0.0 0 0.00 0
FCB 36 ; 3.2 64 0.18 25
FCB 50 ; 4.5 128 0.37 35
FCB 69 ; 6.2 192 0.55 48
FCB 93 ; 8.4 256 0.73 65
FCB 121 ; 10.9 320 0.91 84
FCB 155 ; 14.0 384 1.10 108
FCB 197 ; 17.7 448 1.28 137
FCB 248 ; 22.3 512 1.46 172
;----------------------------------------
;----------------------------------------
*** tables 2 - 5 in here ***********
;----------------------------------------
; Mass Air Flow TABLE 6
;
; TBL = 1.00 * gms/SEC
;
;----------------------------------------
LC6D4: FCB 255 ; TBL SCALAR
LC6D5: FCB 16 ; 16 LINE TBL
;----------------------------------------
; gms/SeC BIN VDC #/HR
;----------------------------------------
FCB 207 ; 206.2 1536 4.39 1591
FCB 213 ; 212.2 1552 4.43 1637
FCB 219 ; 218.1 1568 4.48 1684
FCB 226 ; 225.1 1584 4.53 1737
FCB 233 ; 232.1 1600 4.57 1791
FCB 240 ; 239.1 1616 4.62 1845
FCB 248 ; 247.0 1632 4.66 1906
FCB 255 ; 254.0 1648 4.71 1960
FCB 255 ; 254.0 1664 4.75 1960
FCB 255 ; 254.0 1680 4.80 1960
FCB 255 ; 254.0 1696 4.85 1960
FCB 255 ; 254.0 1712 4.89 1960
FCB 255 ; 254.0 1728 4.94 1960
FCB 255 ; 254.0 1744 4.98 1960
FCB 255 ; 254.0 1760 5.03 1960
FCB 255 ; 254.0 1776 5.07 1960
FCB 255 ; 254.0 1792 5.12 1960
;----------------------------------------


Bob

-----Original Message-----
From: owner-gmecm at esl.eng.ohio-state.edu
[mailto:owner-gmecm at esl.eng.ohio-state.edu]On Behalf Of CSH-HQ
Sent: Friday, July 23, 1999 3:24 PM
To: gmecm at efi332.eng.ohio-state.edu
Subject: Re: a MAF too small


I'd look real close at what the min rate the MAF will accurately sense 
before, running out and buying injectors to try this.
  I thought the Hacs showed a min, and max frquency?.
Bruce




>At 01:18 AM 7/22/99 -0800, you wrote:
>>Isn't the problem not that your maxing the MAF sensor, but that you are
>>maxing the computers internal airflow variable at 255 g/s?  It's a
>>frequency MAF, right?
>>
>
>The 1986 to 1989 Corvette, Camaro and Firebird use a Bosch MAF sensor that
>is a 0 to 5 Vdc sensor not a frequency type sensor (like that used on the
>1994 and newer Corvette, Camaro and Firebird).
>
>One thing you can try is using two stock MAF's is parallel with the ECU
>only connected to one MAF (but air flowing through both) and then using an
>injector twice the size the computer thinks it is. It is VERY important to
>design the air intake so that the same air flow goes to both MAF's - test
>it on a flow bench with a voltmeter if possible.
>
>
>Jason
>
>