Re: 165 $6E cold idle

["Bob Wooten" <r71chevy@earthlink.net>]

> 
> I'd really look at the code/hac before relocating the MAT.
	No worries!!
> In some cals., it's used for figuring the air density entering the motor. 
	Maybe this is my shortsightedness.  I assumed (i know, i know, ass u me),
that the 
air temp had to be used in the formula for calculating the density of air. 
the temp has 
a direct & significant affect on the density of the air going into the
motor.  which partially 
explains why the cars run better in the evening (as you pointed out).  I
guess that i have to
figure out what cal my car has.  I am not sure how to go about that.  Or i
guess that i can just 
start over with the ANHT that Bob V set me up with & take it where it leads
me.  @ least this way
I will have the hac to lead me, thoughts?  I guess i am still a bit
confused on how several cars can
have the same ID (8D) yet use such different algorithms to calc inj on
time.  never mind, bulbs coming
on now.  different application, different hardware, different affects of
some things (Air temp) to 
actual operating characteristics of the motor (aka, do what the motor needs
not what.........., sounds
familiar right?).   however getting back to the topic, air temp is still
basic to the density & 
significant to the air ratio (as BobR pointed out in a following reply).  I
would assume that
this is @ the base of the algorithm for IOT.  

> Might even allow for some heating of the fuel.  In some applications is
used
> for EGR stuff.   The Fuel has a number of different temps for when the
> various light **aromatics** boil off so you can maybe generate a richer
> condition in one operating set of conditions and then really fubar things
> for when things turn suddenly cool.  I'd strongly suggest doing programing
> changes for calibration fixes rather then mechanical patches for software
> fixes.

	I agree, just making comment on the observation.
> Relocating the MAT, for something like this is taking an instant step
back 3
> years to when the hacs weren't available, IMO.
> 
> Some cals., do not make timing corrections for MAT, which is a much more
> important issue in my opinion.   If your seeing an improvement in
> performance you much isolate if in fact it's fuel or timing.
> 
> Just by example:
> 
> On a hot day you lose performance,
> fuel is hotter, and the octane will vary, higher temps., faster boil off
of
> the lighter stuff in the fuel which is what generates the Octane
> (primarily).  So in that respect you need to richen the mixture a lil, and
> retard the timing, BUT in order to recover the differences in pumping
> changes, you'd want to increase the timing (the above at WOT).  Then if
your
> running EGR, is another whole barrel of snakes.
	I think that i see your point.  make one change @ a time & see what is
really
affecting what.  if I make too many changes (or make a change that makes
two 
affects instead of one) then i don't know what affected what.  in this app,
I think that
the assumption that i am making is a good one.  I have taken air from
behind the radiator
& now am taking it from in front of the radiator.  two runs 20 minutes
apart (no significant 
track change), car in D (no shift differences) record times etc from track
& temp differences from
MAT & see what performance difference there is.  if i go on a Saturday that
they are having 
grudge races i might be able to get 3 or 4 runs in in an hour & do a hot,
cold, hot, cold & see 
if the test is repeatable.  OR if this is all for not & am wasting time. 
if they are not using
the temp then for density cal then maybe there is something to not having
to use it, but 
that just rubs me wrong.

> Are you really up to the challenges of the above to get it right?.
	as i see it this is not about fixing anything (don't think that there is
anything broken)
but about learning why it does not work the way that i think it ought to. 
Heck, maybe
i have the wrong MAT in the darn car & it does not work @ all & the motor
is running fat enough
to foul the plugs black (hmmmmmmmmm, mental note check plugs before going
back to the track).

> For the time diddling with the above, you probably could spend the time to
> figure out the best answer.
> HTH
	always helps, thanks Mucho.
> Bruce
>
	BW
> 
> 
> 


--- Bob Wooten
--- r71chevy@earthlink.net
--- www.r71camaro.homestead.com



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