88h & hi-way stuff

[rr]

No such luck. However, if you do not mind losing open loop decel,
it should be easy to add. I'm working on it. I've checked a bunch of
bins and so far only big blocks use this feature. The problem with the
'747 is lack of room. If the '747 is used on a non-egr vehicle, a whole
bunch of room opens up. However, I'd rather come up with a egr
friendly solution.

BobR.

Kevin R wrote:

> I know I asked this before, but any chance the 7747 has a hiway fuel to go
> along with the hiway spark?
>
> Kevin R
>
> >
> > 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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