Dual TBI setup

[nacelp]

OK, play a word game.
HP is just a matter of toque at a specific rpm.  To proper size things you
want to make sure you can cover the max HP, plus allow a little flow for
slightly over that, to allow for shifting.
  So when sizing for injectors other then a lawnmower or some other ultra
low speed application all we have to really go on is HP.
  To get toque is a matter of engine components, and just about has nothing
to do with even mentioning EFI or carbbies.   Torque is getting really good
VE numbers at a low rpm.  All that matters is things condusive to that, for
what your doing.  If you want gobs of torque, then your going to want to
keep the air flow "high+ active", meaning a rather small carb, as opposed to
a 850 CFM Holley or dominator.
  Not looking to start a thread about the the virutues of BBC Torque.
Anyway,  I've easily gotten 325 with a mild BSC with just (2) 2"
butterflies.  This was using 2-90 lb/hr, BBC injectors.
90x2=180 (total lbs/hr)
BMFC .5 gets 1HP per .5 lb of fuel per hour
so the means 360 with a moderately tuned engine, done really right I'd think
you could get to .45 or 396 HP.  Then running the FP up some should be about
400+ HP, well within your target zone with one TB.

Trying to run 2 BBC TB on your combo would be like running a dominator on
it.
If you have to run two then use something closer to the 400 neighborhood

I ran two single barrel TB with both single and dual IACs connected.  If I
knew then what I know know I'd run both, I think.  Running just one TB lets
ya use the 747, if you have to run two then you need a driver board, or to
use the 749.  I would be ALOT easier for you to stay humble, and matter a
single set up first.
Grumpy

> QUOTE:
> How much honest HP ya wanna make?.
> Grumpy
> > Has anyone ever tried (or know of someone who did) a dual OEM TBI setup
on
> a SBC?  Just throw it on a dual carb-type single plane manifold.  Someone
> mentioned it on the Third-gen board and it has really got me wondering.
By
> itself a single TBI won't pull in the air or inject the fuel to keep a 383
> going, but a dual setup would...  I wouldn't think that there would be too
> much to "fab" up...  some linkage, something to monitor/combine both TPS's
> (or just run one)... anything else?  Maybe just block off one of the IAC's
> and let the computer just control the one...  I'm interested in this
because
> > I happen to already have two of them, and don't want to shell out the
cash
> ($2000'ish) for an Edelbrock/Holley system..
> REPLY:
> Well, just shy of a thousand would be nice.  Seriously, I really aint
> looking for HP, rather have torque (450ish).  What do you figger this
would
> get?  The TBI's from the 454's flowed (correct me if I'm wrong) around
> 640cfm - So that would theoretically flow about 1300 with two of 'em.  I
> would think that would be plenty of air, as for fuel - I don't know.  I've
> been looking through my archives of this list for that thread a while back
> that stated what these injectors flowed but I haven't found it yet.  I
think
> it was something like 80 lbs, but don't quote me on that.  If that is the
> case, 80 X 4 is a bit of fuel...  I believe someone also posted the amount
> of flow per horsepower but I haven't found that yet either.  Do you think
> the ECU would handle it?  Looking forward to your thoughts...
> Steve


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