Re: Off idle transistions

["Bruce Plecan" <nacelp@bright.net>]

> That's great info and I appreciate you sharing it with me. I think you
know
> I have the 747 ECM but the chip currently in it is not the stock config
from
> TCity.

Do a file compare, and check back.
Or forward me a copy, and I'll see what shakes.
I will not archive it.   Justa gander.

 They sent me another one once I was able to report back on the result
> of the drag strip and dyno runs. I believe that the stock chip was causing
> the knock retard to be invoked big time at the top end especially in the
hot
> weather I was running in. I am hoping to get a bin file of the stock chip
so
> I can compare to what I have now because the stock settings didn't seem to
> be that rich. Having said that, it appears that part of the rich condition
> both at cold start and cruise was the fault of unbalanced TBI units which
> have since been balanced. Yesterday, I bumped Fp to 10.5 and it seemed to
> make idle smoother although there are still times when idle will hang up
> there until IAC's bring it back down.
> And speaking of balancing TBI's, Bruce, you mentioned that your Xfire had
> the 2" units as does mine. Were you able to retain the slot in the venturi
> used for the balancing of the units?

heehehehehehe,
Manometers, Takes a Mercury one to do it right.  Motorcycle shops used to be
able to sell them before Mercury, never mind
Anyway, just use a 1/4" piece of fuel line, and hold it near your ear, and
compare the level of noise from one to the other, then adjust min throttle
openings as necessary.  BTW, that's a trick from the Stromberg 97 dayz.
Then from the transistion slot (on each connect them) run a piece or 1/8" ID
vac line.
Bruce


 If not, what did you use? I drilled
> vacuum port which was in base and connected to center port of TBI. I am
> assuming that it is now reading manifold vacuum. A water manometer is
> useless.
>
> Dominic
> ----- Original Message -----
> From: "Shannen Durphey" <shannen@grolen.com>
> To: <gmecm@diy-efi.org>
> Sent: Tuesday, August 15, 2000 6:48 PM
> Subject: Re: Off idle transistions
>
>
> > Dominic Sorresso wrote:
> > <snip>
> > > Also, cold start
> > > seems to be richer than necessary until it goes into CL.
> > >
> > > Dominic
> > Dominic, I've never seen a crossfire car that didn't run rich in OL
> > with the original ecm.  Most are so rich that they will foul one or
> > even two plugs.  It would make sense to think
> > TC is using the stock calibration as a base for their fuel and spark
> > tables.
> >
> > Regardless, when I converted my pickup xfire to 7747, I found that the
> > stock (7747) fuel tables for low MAP were very close, but that I've
> > had to add additional fuel to prevent backfire during acceleration,
> > when not in pe.  I started with a stock 350 cal, changed the injector
> > constant, and went from there.  One other thing I did was collect as
> > many manual trans 7747 calibrations that I could,  plugged each one
> > into the truck, and picked the one that idled the best.  Something
> > about re-inventing the wheel... From there I set the injector constant
> > so it matched my engine displacement and injector size, and started
> > driving around.  I kept track of bl and integrator #'s, and moved the
> > injector value a little bit more to reduce the CL corrections.  After
> > that, everything has been done in fuel and spark tables.
> >
> > At this point I'm wishing that I'd had springs added to the 57 spec
> > clutch.  She'll start to slip if I'm not careful.  It was never meant
> > to be this way...
> > Shannen
>
> --------------------------------------------------------------------------

> >
> >
>

>