TBI with TPI ecm???

[Walter Sherwin]

If  *just* looking for better ALDL performance, then what about some of the
newer TBI specific boxes that actually support 8192 ALDL baud?  Would give
you a firing scheme appropriate to the TBI theme you are running, plus what
you are after.  The batch TPI boxes, when using TPI oriented software, tend
to fire according to SSDF or SSSF schedules which is not what you want for
TBI  (unless you are currently running out of top-end RPM BPW headroom).
Electrical driver versus injector compatability will also be an issue, when
using a TPI box & software for TBI, unless appropriate hardware jumpers
and/or external driver boxes are added.  IIRC most post 94 TBI boxes were
8192.  I am sure that there were others even pre '94.


Walt.




> Actually what I was wondering is how much is involved in using one of
these
> ECMs to control a TBI system, in particular a crossfire. Just seems that
> both the speed and number of parameters output to scanning software is
much
> better on later SD TPIs than the TBI (currently 747) ones, which could be
> helpful.
> Since they basically fire two banks of injectors I was wondering if using
> one to fire two TBI injectors is just a matter of tuning the prom tables
or
> if there's more to it.
>
> Kevin R
>
> > Are you asking if you can obtain a TPI ECM and configure the hardware
> > and software for a TBI?  If so, there are many ECMs that can support
> > both modes.  For example, the '7730 has been used for both TPI and TBI
> > applications (with different software though).
> >
> > Or, are you asking if you can use a TPI ECM configured for TPI but
> > driving a TBI?  If so, then the answer is almost always no.  With a TBI,
> > you have to fire the injector(s) once per induction event.  The TBI uses
> > the airflow through the wet manifold to route the fuel to the correct
> > cylinder.  If you fire the injector(s) at the TPI rate, some cylinder(s)
> > won't get any fuel.
> >
> > --
> > Ludis

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