Using TBI on moded 5.7

[Mike Vannorsdel]

I'll keep messing with it hope to find something.  The part that really bugs me
is no TPS adjustment.  It's possible I'm looking in the wrong spot.

CSH-HQ wrote:

> Just hate it when I can't pick a post apart <g>.. Good info., and seems
> to line up with what I've found.
>
>   If you want to get a rough eye-ball on the spray pattern/quality, just
> use a timing light off of 1-6 ona SBC.  Will give good clearty about where
> the cone ends, and if the injector is dripping heavily when it should be
> spraying (really large gobbules).
>
>   Also, if you machine for bigger butterflies, you'll need to do the above
> to set the spacing for the injectors.  When you install the larger
> butterflies the "cone" winds up totally on the buterfly instead of at the
> "air gap" where the butterfly is closest to the throttle bore.  Going from
> 1.8s to 2.0 took raising the injectors about 1/8" inch...
> Grumpy
>     Was getting to want to almost bypass the Smokey Ram, and go TPI, but this
> SR, 730, and high pressure injectors is starting to sound really
> good/different...
>     Might have to get the 200R4 finished, change gears, and tighter
> converter now!!
>     Hey Doc, where's the Predisone?.
>
> >Mike,
> >I cant guess what you may find wrong, but I
> >wouldn't worry any more about "fuel puddling".
> >All of my family fleet of TBI's (one Astro, 2 PU's)
> >puddle as they should.
> >
> >One of the early 80's SAE papers on TBI
> >0098-2571/80/8810/0102 SAE, Inc
> >included a paragraph on "fuel pulse smoothing"
> >and it had the following things to say about
> >this area.
> >
> >Re-phrased snips from paper:
> >
> >1)  Placement of injectors above the throttle
> >bores/throttle blades is proper to smooth
> >injector pulses over time.
> >
> >2)  The throttle bore walls and throttle blades
> >will accumulate fuel in a sheet that will flow
> >toward the openings around the circumference of
> >the throttle blades.
> >
> >3)  At idle and part throttle (MAP less than
> >60 kPa) a sonic pressure ratio will exist across
> >the blades and this will violently shear off
> >the fuel sheet at the openings around the
> >circumference of the throttle blades.
> >
> >4)  This violent mixing of fuel and air promotes
> >good part throttle distribution and is considered
> >as a "design feature" of TBI.
> >
> >Where TBI struggles is when the manifold is
> >re-pressurized rapidly (rapid change in throttle
> > opening) and a fuel film can/will condense
> >on the manifold walls - Part of the reason that
> >extra fuel (acceleration enrichment) is required
> >and why so much of the TBI passages are heated by
> >hot water.
> >
> >Bud
> >
> >----------
> >>From: Mike Vannorsdel <vannorsdel at rmi.net>
> >>To: gmecm at efi332.eng.ohio-state.edu
> >>Subject: Re: Using TBI on moded 5.7
> >>Date: Mon, Nov 8, 1999, 7:01 PM
> >>
> >
> >> I can actually see puddling on the throttle plates at idle.
> >