Re: EPROM tuning head start

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

> Some thoughts on this (7747) tuning methodology. From the tuning tips it
> appears that spark timing is the first to tune since the BLM can keep the
car
> running even without a "perfect" fuel map. If you don't have a scanner or
> Diacom, could you use a DVM on the TPS, a vacuum gauge and a tachometer.
Do a
> run and keep the vacuum and tach steady with throttle (TPS).

NO.
The vacuum is greatly effected by timing
Just do what's there to learn what your doing, don't try and over analyse
things in theory before you even start, you'll be chasing things in circles
thata way

Note TPS value
> that this takes. Advance timing in the spark table corresponding to the
> vacuum and RPM. Do run again and watch for a significant increase in TPS
to
> keep car at same RPM and vacuum. This would indicate knock retard I
believe.

See your already doing it, assuming
BTW your trying to so something 180d from suggested.

> Back off timing and do run again to make sure of max. timing before knock
> retard.

Your again doing it backward.  You want to start with as little as timing as
possible and gradually +- timing, AND fuel, till you gett things dialed in.

 Do all cells of BLM this way, assuming the BLM cell boundaries are
> known. Then, drive car until all BLM cells have had a chance to settle in.
> Then note the value of each BLM cell away from 128. Now, is there a way to
> correlate the amount the BLM is away from 128 to the amount needed to
adjust
> the VE vs. RPM vs. MAP table?

No, other wise we could tune each others car by phone.  You have to "tinker"
with what your engine is asking for.

If the goal of tuning is to get the BLMs at 128
> or slightly smaller, why not let the BLM tune for you and get you homed in
> much faster?

???
+- the 128 is how far the tune is off.
Gettin back to the old aftermarket joke of just setting the BLM limits to 70
amd 170.  Works in a fashion, if having the engine **just run** is what you
want.

If the BLM is at 120 in a certain cell, why not remove a
> specific amount of VE from the table to increase the BLM by 8 points?

That's what you supposed to do.

 If this
> is possible, anyone know how much VE corresponds to one point in the BLM?

After you get familiar with your combo., you get a feel for it.
I start roughing things in with 10% changes, and then less and less %
change.
Grumpy

> This may vary by RPM, MAP, etc., so any comments on the concept? From here
> check the BLMs once a week and adjust VE to move BLMs back to 128. Tune
WOT
> standard way.


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