DFCO, What is it good for?

[Bruce Plecan]

-----Original Message-----
From: Mike Pitts <mpitts at emi.net>
To: gmecm at efi332.eng.ohio-state.edu <gmecm at efi332.eng.ohio-state.edu>
Date: Sunday, March 21, 1999 12:04 AM
Subject: Re: DFCO, What is it good for?


>>Some time ago was a thread about my comments about setting things up with
>>min IAC counts, and I was taken to task for that statement.
>>Is there a way to raise the anti-stall rpm on the 148s?.
>
>I've don't recall a specific anti-stall section in the cal.   It's probably
>not labeled as such, but rather IAC recovery rate or something.  I'll
>have to take another look.

On some other stuff, it uses a 300 rpm cutoff, if that gives a hint.
>
>I personally have never had any luck messing with the IAC count or
>rate stuff myself.

Gee, I'd like to hear of someone having success with messing with them.
>
>This about-to-stall situation happens at the same time as I've seen the
>O2 LED bar meter go to zero in a friends car.  That's why I think it's the
>DFCO.
>I noticed in the cal that DE is set slightly leaner when the TCC is locked
>up.  I gather from this that decel can go leaner if there is sufficient
>engine
>braking occuring from the force of the trans.
>
>Since I don't have a TCC anymore and my converter is a light 9", and
>since cars with 9" converters tend to stall easily, I'm guessing the engine
>is leaning out too much during decel.

Ohh, drivetrain inertia issues.  Yep, inna heart beat.  That extra few
quarts of
ATF make a difference.  On the sy's they flash a couple 30 msec injector
pulses
during overruns if thats new info., like every 5 secs or so, less than like
30mph.
These numbers off the top of my head, I ya want better sy numbers I can fire
up the bench, and try to get a better read.
Bruce
>
>-Mike