"Tri-power TBI's

[andy quaas]

Maybe you could use the TBI in the center (primary) with any ECM of
your shoice and wire it up as a closed-loop speed density system. 
Then you could use the same type of linkage that opens the secondaries
just like a stock tri-power.  The secondaries would run off of one of
those wierd systems that use only RPM and TPS (no O2 or MAP, like the
analog projection from holley).  You don't want to have 2 O2 sensors. 
Or maybe you could just run 3 small TBIs (with all throttles tied
together) and one ECM, one O2, etc.  That would probably be the best
setup for tuning and i don't see the throttle response being bad
because of it.  If superior response is asbolutely nessesary, than you
could just make a throttle linkage that opens the secondaries a
teeeeeny bit later than the primaries.  But if the TBIs are sized
properly, there shouldn't be a response problem.  I don't think you
want to get into 2 separate systems trying to run one engine.  

Andy


---Greg Hermann <bearbvd at sni.net> wrote:
>
> Seems to me that you might be able to make a tri-power TBI set-up work
> quite well using something like the computer from a four-cam Vette.
> 
> Run the center unit injectors as the primaries, run the end units as
the
> secondaries, and use the drive by wire actuator which normally
operates the
> secondary throttle on the Vette to operate the end TBI unit throttles.
> After all, none of the stock tri-powers were mechanical linkage
throttles
> anyway!
> 
> Doesn't have to be a Vette computer--just something that could be
> programmed that way and with the right sort of I/O capabilities to get
> there.
> 
> You could even use the "valet key" feature--lock out the end units
until
> enabled.
> 
> Seems to me that this approach would have the computer knowing
EXACTLY what
> was going on, all the time. And it sure is a way to get the benefit
of efi
> on a classic (looking and sounding) Poncho engine! I have no quibble
with
> the fact that an IR setup might run better-but the point was more
like how
> to use an existing tri-power manifold.
> 
> Regards, Greg
> 
> 
> 

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