Re: Holley 4barrel TBI, 700 cfm or 454 TB? Q's

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

>Obviously I need a bigger TB, I thought surely the 670 cfm would feed my
> motor till I discovered at 1.5inHg it probably flows just under 500 cfm
> which im not sure will be enough to feed the top end monster this motor
was
> built to be.

Now you claim a top end monster.
Then you shouldn't be playing with a TBI.
Two 2" butterflies done right make 325 at 5500 easy

> My other option is a holley analog (doesnt have an IAC motor)   4 barrel
TBI
> unit, with 65 lb injectors, brand new for 175 bux.  I like this one
because
> it surely will feed my motor since its measured at 1.5inhg (not 100% sure
on
> that but I think so) also because this should feed the 350 or 383 im
> planning to build next eventually. I can also run it withoutany adapters,
> andstill have hood clearance to experiment with spacers.

All ya need to do is make an injector driver board.  Then you can use a 730
to drive it.  Then drop to 55 lb/hr injectors, and try to get it right.

The only problem is
> wiring the injectors It seems. Ive heard that wiring them in series can
> cause erratic performance of the second injector in line.

I do think you've been here long enough to have caught all the banter
before.

> I noticed a while back that my ecm seems to have four wires going to the
> injectors.. two of which tie back in to the wire next to it. Its my
> understanding that the ecm simply uses these wires to ground the injectors
> and this is how it controls them.

Two wires going to injectors oem.  Two of the injector wires go to the fuse
box.

> So I guess my questions are A) Can the 454 TBI unit really feed my motor?
I
> want this thing to just rip from 5000-6000 like I felt it do with a holley
> 600 cfm carb
> B) If not, are the things ive heard about wiring theinjectors in series
true
> on the 4 barrel?  If so, how hard would it be to fashion a powersource
> forthem, and can i just use those two extra spots on my ecm to control
them?

A alreadyy answered
B you need to look at a wiring diagram. your confused about something.
> (assuming my understanding of how the system functions is correct)
> C) Will running sans IAC motor have any real bad effects other than just a
> little sacrifice in idle 'driveablity'?

A little?.  If you mean not running when cold your about right.  *Even*
Holley uses a kicker solenoid for cold idle.
Grumpy

> Any and all opinions (good or bad) welcome
> Pablo


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