747 & 4cyls

[Garfield Willis]

On Tue, 22 Aug 2000 15:37:09 -0400, "Bruce Plecan" <nacelp at bright.net>
wrote:

>The 730 and 165 have been used in single injector TBIs, but no hacs

Okay, yeah what would be ideal is an ecm with a TPI mode suitable for
4-cyl, AND that had been fully hac'd. You mean to tell me no such
animal yet??? Shriek, gnash, argh, whimper!

>For the 4 cylinder distributor set up the syclone code, might be a good one
>to look at.

OK, das good.

>The 4 DIS is another matter, that applications does exist, just I don't know
>of a hac for it.
>On thing that has been tossed around here is using the sy code DIS, but it's
>not working yet.

Well, ya know, we CAN get by with the built-in advance curve in the
DIS module, without EST support, so as long as we can hand a clean REF
back to the ecm, we could get by with just fueling being done with
ecm.

>Ya, things are all bolted in, and she drives, just got bugs to work out,
>just need to put some time in on her.

Great, drop me a pix privada if you're not up to uploading to ftp.
Let's have a look at that FWF (XA-speak for firewall-forward :).

>Ohhh, I was thinking like 2-3s that high, like approaching needing O2

Yeah, that's what I suspected, but XA guys fly mostly VFR, and you
have to be logged into the IFR system and under strict ATC supervision
if you fly above 12k, which is near the O2 requirement alt also. The
way you figure it is a lapse-rate of 1"Hg(0.5psi)/1000ft, so you're
losing 6psi off MSL ambient at 12k ft, so your WOT abs press would be
around 12psi instead of 15psi at MSL, and taking into account the
pressure drop in the induction, that means the actual change in
absolute MANIFOLD pressure is about 10psi compared with 13psi, or
about 10/13 = 77% of max power. We use the ruleOthumb of 75% of max
power. But since speed-density gets the density and air mass directly
from IAT and MAP, except for the exhaust pressure errors, it simply
thinks we're sucking only 75% of maximum, and fuels accordingly. So it
ends up pretty close; at least "close enough for who it's for". :)

>Just having trouble unthinking what you need.  The auto application is like
>totally different, in execution.

Yup, the principals and parameters are all the same, but the tradeoffs
and execution, as you say, end up having some interesting differences.
The contrast is what makes it fun in large part, and helps to divide
the essentials from the artifacts. Boats, airplanes, and land
vehicles. Much in common; but mucho differences too. Fun stuff.

>Forum, just don't tell me committees meet there

Worse. I was thinking of that old flick titled "A Funny Thing Happened
to Me on the Way to the Forum", a farce about Roman society. Strange
how ours and their society are running so parallel. Heh.

Garferkle


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