Re: Tuning Tips questions

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

> Here's a couple of questions on your tuning tips dealing with the light
> cruise section,

Don't over analyse.   Don't make it more complicated then it is.
Now with that said

> 1 Once you have determined TPS signal at 40Kpa, you suggest adding
> timing at that 40Kpa and RPM cell. The re-test at original TPS signal
> to determine "new" vacuum value. Do I now +/- timing at "new"
>Kpa/RPM cell or go back to 40Kpa?
>     What increments of timing would you +/-?

Nope, it's tps vs MPH,
look to see where you are K/Pa just to know where to make the timing, or
fuel change.
  I cut things at 2d, unless there are initially no change or the figure is
just
grossly wrong (that only comes with experience)

> 2. When you say "drop off" as little timing between 40-50Kpa up to WOT
> (100Kpa), what increment per cell are you suggesting. What should
>total drop off be?
> For example, At 1800rpm and 40Kpa, value is 24.3. At 100Kpa, value is 6

Depends on car, and driveility.  No way to forcast what your engine is gonna
like

> 3. What about cruise range within +/- 200rpm of the initial 40Kpa
benchmark?

Depends on lots of variables.
What resolution is the table you working at and what are the break points.
If the steps are 1200, 1600, 2000, then I'd run the cruise mode testing at
those steps in addition to what ever your cruise is that your concerned
with.

This is way you get into so many reburns to get it right.  You have to look
at the resolution of the table and kinda experiment around where ya want to
be so that you can smoothly transistion to those conditions.  Like do you
baseline testing on flat ground, and try to do it in both direstions, to
account for cross winds, mild grade changes etc..   Then move toward lite
grades, and then larger ones.

> I hope these questions make sense. they'll at least start giving me a
> clearer picture of how to start?

One change atta time, and notes.  That's all you really need.  Document
Document document  the easier it is for you to see trends developing the
quicker you'll be done, and ready to do another car.
Then you'll see the )(#$)@#(    )#($#()#@    mistakes you made on yours, and
go back and fix yours.   Then ya help someone else, then again, it's aww
$hit, and fix yours.   It's a continual learning cycle.  Sometimes just a
silly like comment from one of the other guys, and it's aw darn, that's
whats going on.
Bruce

> thanks,
> Dominic

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