Dual TBI units - How To Handle Twin IAC's?

[the Fredericks]

I now have a few CS-452s; I'm doing ECM conversions with them.  If anyone
wants a *few* of them, email me.  These are the P&H drivers from Cherry
Semiconductor.

Kendall Frederick

> -----Original Message-----
> From: owner-gmecm at esl.eng.ohio-state.edu
> [mailto:owner-gmecm at esl.eng.ohio-state.edu]On Behalf Of
> cranford at texas.net
> Sent: Friday, December 17, 1999 3:17 PM
> To: gmecm at efi332.eng.ohio-state.edu
> Subject: Re: Dual TBI units - How To Handle Twin IAC's?
>
>
> Walt...
>
> Can ya give more details on the external P&H driver box?  That's
> exactly what I
> remember reading about a little while back in another thread, but
> couldn't find
> again!  This idea is really starting to come together with ya'lls
> help!  Thanks
> for all the input so far and keep it comin' please!
>
> Stephen
>
> >
> > Perfect timing for this discussion thread..........
> >
> > Just days ago I ordered a brand new 454SS TBI unit from GM (17112570 aka
> > 17091047),  to feed the second of two screw-chargers that will
> live together
> > atop my 454.    I'll be converting both TBI units for 30psig
> fuel pressure
> > operation (17113079 regulator),  in order to feed the peak airflow
> > requirements, and I intend to control both TBI's simultaneously via the
> > stock 16147060/BAMY PCM  together with an external  2-to-4  4/1 amp P&H
> > current driver box.
> >
> > At this point everything regarding the project has been planned
> out in great
> > detail,  EXCEPT for the twin IAC issue.  I am still in the
> midst of "head
> > scratching" as to what I will do about this.  I could cheat,
> and just drive
> > one IAC via the PCM, but,  I would prefer to drive both IAC's
> via the PCM
> > for mixture and pressure balance reasons.  Here's what I am
> > wondering............
> >
> > 1) Can I physically drive two IAC's from the single PCM IAC driver?
> > 2) If so, should I wire the two IAC's in parallel?
> > 3) For a first blush at the cal, can I simply cut the commanded
> IAC steps in
> > half?  Just looking for a starting point.
> > 4) Any other thoughts or recommendations?
> >
> >
> > Thanks a bunch;
> > Walt.
> >
> >
>
>