EFI Pow Wow, Wow

[Bruce Plecan]

> >I'm big into trailing throttle stuff, for vehicle coast down, and on
> >the turbo stuff keeping some heat in the exhuast so that when you do a
roll
> >offf, and on the turbo can spool right up.
> Could you say more (for those who couldn't be there, whimper) about
> what things you do in the ECM programming for the above?

There are at least six different worlds ref Trailing throttle, meaning
closing the throttle for slowing down (gonna be real basic here so as many
as possible get it, since it seems to have been ignored).  For the moment
and not to generate a 30 page discourse about it, I'm gonna cover how I SEE
things and for N/A, Turbo, and within each, Drag racing, Road racing, and
street.
Also, gonna be general about the ecm since the ways they handle it differ.

OK, in Drag Racing the worst issue is handling Over run during the burn out,
you want the engine to decclerate rather quickly, and turning off the fuel
is an OK way, trouble is you can still put alot of head in the heat.   If
you leave the DFCO on, then just be sure to take alot of timing out, so what
ever fuel is there, goes to cooling the chamber, and then turns off early
enought to make sure and overrun stall doesn't accure.

Then we have road racing.  The only way with the tubos car to run really
well IMO is with the DFCO off, and set the over run fuel just a tad leaner
then the next row ie use 10-15% less fuel at the 20 KPa level then at the 30
KPa row.
Crank alot of timing out of the chip in that same area.
That will help to keeep the EGT up, and then it will spool up quicker on the
next throttle application.
   The N/A are similiar, but alot more timing is taken out to help with
engine braking.  If you drop too much fuel out then, there is such a poor
fire that is worsens the engine braking.

    On the street things get even further divided since your much more into
driveability, and trany type makes more of a difference.
    **Generally**,  if you can greatly acclerate the IAC decay rate you have
the issue handled,  if not then try limitng the max IAC count (not for
choke).
    Shouldn't really be a problem with DFCO on a manual, and the converter
is gonna play a big role in this.

> >Time talking about TPS PE, and TCC release stuff

TPS vs PE enable
and
TPS vs TCC release is all about drivibility and the parameter of car.

If you looking for economy you generally want to min rpm, and hitting PE, so
you set it rather high, so as not to enter it often, if you want to drop the
gun at all the lights, and take off like a shot then you'll want it as soon
as possible, and min delay.  Some cals have a weird setup like % TPS, and
then a time to apply value.   Then on some of the heavy trucks they have a
high TPS enable, and the as much as 25 secs till apply.

On the TPS TCC release, you want it high enough so that you not having the
tranny hunt all the time, and then low enough that on a grade your not
detonating the motor cause you lugging it down to far.
I'd also try and look at things to get em so that your slightly higher then
max torque, when it unlooks or close to it as possible.
  Again getting into preferences.  For a *hot* one, then you want the engine
never to lug down.
Whew
Bruce

>
> Can I also beg for a brief outline of the discussion on each of the
> above? I know you can't play back the whole two days, but maybe just
> some high points. I'd also be curious about what AFRs you saw with the
> WBO2 equipment during AEs and PE.
>
> Gar
>
>
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