calculating load value

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Jun 19, 2003 | 09:24 PM

NastyL98_T/A

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From: Severn, MD.

Car: '88 T/A and '90 T/A

Engine: LB9/383

Transmission: T5/700R4

calculating load value

Can someone tell me how to calculate the load value based on MAF volume vs. RPM? Is there an equation to do so?

Jun 20, 2003 | 06:21 AM

RBob

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From: Chasing Electrons

Car: check

Engine: check

Transmission: check

Re: calculating load value

Quote:

Originally posted by NastyL98_T/A
Can someone tell me how to calculate the load value based on MAF volume vs. RPM? Is there an equation to do so?

It is basically LV8 = airflow / rpm.

The code is a little more involved:

Code:

        ldx     *L0099          ; Current Minor LP Ref Period
        ldd     *L00F1          ; DISPFLOW, Mass Air Flow gm/sec
        jsr     LF429           ; 16 * 16 Mult routine
        pshb                    ; Save Middle 2 Bytes of Product
        psha                    ; Save Middle 2 Bytes of Product
        tsx
        ldaa    LC5B0           ; Ld VAR FOR SCALING LV8 Scale factors
                                ; 80d = 80/64 = 16
        jsr     LF5B5           ; FACTOR IN 8x16 MULT
        ldd     0x00,x
        rolb
        rola
        bcc     LD742           ;
                                ; ... else
        ldd     #0xFFFF
LD742:  lslb
        adca    #0x00           ; ROUND
        pulx
        bcc     LD74A           ;
                                ; ... else
        ldaa    #0xFF           ; USE MAX VAL
LD74A:  staa    *L0064          ; FILTERED LD VALUE (LV8)

The minor LP ref period is the inverse of the RPM. So here it is multiplied by the airflow, then scaled and saved.

RBob.