88h & hi-way stuff

[rr]

Here is the info to enable & setup the hi-way spark and fuel
on a mask 88h bin. This mask is used on the '730 powered
3.1L f-bodys', along with a myriad of fwd 3.1 & 3.4l stuff.

The way it works is that hi-way spark needs to be present
before hi-way fuel is considered. The user option word at
prom address 0x6B8 has two qualification bits. They are:

10h    if set, tcc needs to be locked for hi-way spark
02h    if set, must be in high gear for hi-way spark

After that, the following are checked:
;
; --------------------------------------
; HiWay spark quals
; --------------------------------------
;

0x8088 224 ; max map, 90Kpa (Kpa = N * 0.3125 + 20)
0x8089 147 ; min coolant (70.25øC)
0x808A 48 ; min rpm (1200)
0x808B 2 ; timer, sec's
0x808C 0 ; timer, sec's

The next table defines how much spark is added:

0x808E  ; HiWay SA table vs. map

20    0
25    0
30    0
35    0
40    0
45    0
50    0
55    0
60    0

Hi-way spark values of 0 disable the hi-way fuel. So, set to a
minimum at 1/3 degree of spark.

The option bit at: 0x6B9, 80h, set to a 1 enables hi-way fuel.

Once hi-way spark becomes active, hi-way quals are tested. They
are nothing more than the vehicle speed.

; 0x872B 48, 50  ; hi-way fuel: mph thresholds, w/hyst

If they pass, the commanded afr becomes:

; 0x872D 154  ; hi-way fuel: afr * 10


Have fun,

BobR.

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