Reference Angle

[Ward Spoonemore]

On Wed, 10 Mar 1999 22:25:40 -0500, Jason Weir wrote:

If there is any offset it would be a time delay and proably less that uesc,
This will not relate direcly to degrees crank, since at say, 3000 RPM, 1
degree = 55 usec. 
Ward
> 
> 
> Ward Spoonemore wrote:
> > 
> > 1. The ECM is active on the falling edge of the DRP, (this is the Dist
ref
> > Pulse).
> > 2. the ECM has a calib val for sorting any static timing lead, 4 deg in
big
> > block, 0 fo small blocks.
> > 3. the ECM obviously can not advance the timing( else we have time
travel),
> > It generates a pulse son number of usec's after the DRP, this
corespondes to
> > 
> > some number of degrees befor the next DRP, (not yet happened)
> 
> 
> Ward,
> 	I understand that the ECM looks for the falling edge of the DRP, but
> that is the signal coming out of the ignition module, what I am asking
> is there a timing difference between the DRP and the actual triggering
> of the mag pickup in the distributor?  So with the timing connector
> disconnected (no ECM advance) and the static timing set a 0 deg, if the
> mag pickup is set to fire at 5 deg BTDC when does the ECM see the DRP? 5
> deg BTDC?  Does the ECM fire the injector and the sparkplug at the same
> time, or a certain time (degrees) apart?  
> 
> 
> > On Mon, 08 Mar 1999 21:45:02 -0500, Jason Weir wrote:
> > 
> > > With all this talk of DIS  and SyTy proms and the reference angles
> > > between the pickup firing and TDC, can anyone tell me what the
correct
> > > angle between the pickup firing and TDC is on a 7747 system would be.
> > > Would this be built into the ignition module or is it adjustable with
in
> > > the code? I looked through the code that I have and I didnt see any
of
> > > the variables referenced by Ted (KREFANGL & KMAXRTRD2) but that
really
> > > doesn't mean that they don't exist.  Due to the fact that my
> > > distributor/pickup  is a non-GM unit and right now I have the pickup
> > > firing as close to TDC as I can get but now I am not sure this is
> > > correct.  just some more food for thought..
> 
> 
> Jason Weir
> -- 
> 88 Wrangler - 155K miles and counting
> 258, 4.0 head, Cherokee header, 2 1/2 exhaust with high flow cat &
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> http://home.att.net/~jweir
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