Custom PCM & Injectors Questions

[nacelp]

Well, I only have slight info., that may help ya here.

> This computer was custom programmed by a company in AZ by the
> name of Z-Industries (I believe) for an owner of a Ram SS/T
> 360 with a Paxton SuperCharger and N2O.  The goal was to increase
> performance for the 1/4-mi. track.  The first computer sent to him
> with the custom program was erroneously put on a Dakota computer.
> At the time, he was told it was for a '97 and, hence, my interest
> and one of the main reasons for buying it.  (MP has never put out
> a hi-po PCM for the '97s).  The '96 and '97 Dakotas are both OBD-II
> compliant but went through a major exterior design as well as major
> differences in how sensor outputs reach the dash gauges.

Z-Industries last I knew was in Orange CA.  I haven't had anything good to
say about them, after my experiences there.
  AZ has AZ Speed + Marine, read about their Carprom deal, and you'll share
my feeling toward them also.  They want you to play a bunch of money and
then tell them where the tables are.

> I do not have the technical specs of the custom program but
> I was told that it was calibrated to run with 30# injectors,
> calibrated for 160F coolant thermostat (stock is 195F with
> most performance Daks running 180F tstat), all delays were
> removed to give instantaneous throttle response, rpm and
> speed limiters were raised, tranny shift rpm points were raised,
> idle rpm raised, prevent detonation for 10lb supercharger boost
> and 150hp N2O shot, etc.

No less then 180, and if the chip is right then 190.  Lots of chips folks
just use the coolant temp correction, as a way to richen up the mixture.
Brillance at it worst.......

> While my surface knowledge of efi is enough to tell me that
> running this PCM on my vehicle is a gamble, I took the chance
> and am taking the time to put it through careful road tests with
> a scanner.

Sounds like you have the right idea.  BTW, FWIW, there is tuning.doc at the
FTP, just might help ya a little.

> At idle, scanner outputs show that timing has been advanced more
> than the MP hi-po PCM and pulse width of 19# injectors is shorter
> than with the MP PCM (I'm looking to see if the scanner can
> output duty cycle data).  In closed loop, the o2 sensor is doing
> its job bouncing readout of rich and lean with longer stays at
> rich.  At WOT (open loop) and initial startup, it shows rich.
> As previously stated, under sudden WOT at any rpm, there is a
> sustained 'bogging' with the 24# injectors, and hence the return
> to the 19s.  Gradual changes in throttle position does not
> cause this problem.

AE, is too rich with the bigger injectors.  Yep, smaller ones, and can you
adjust the fuel pressure?.

> My questions were more of a general nature since I do not have
> any tech specs of the custom program.  It seemed to me that, if
> a program is calibrated for 30# injectors, pulse width would be
> different than a program calibrated for 19# (or 24#) injectors
> as well as duty cycles (???)  I have complete zero knowledge on
> delays.

Your correct in you assumptions.
The delay things generally allow th eengine to get on the cam, or rpm high
enough for Power Enrichment, part of your bog, might be having eliminated
the delay.

> I've tried accessing the archives to see if there is anything
> in these subject areas (does not have to be specific vehicle
> related) but have been unable to access them lately.

Not much Mopar stuff there, the is a zipped archive you can down load.

> If there are any sites in which I can get a little deeper knowledge
> into engine/fuel management, I would appreciate any references.

Rading the archives, is about as good as it gets.  Specially for refering to
Books, etc.
Grumpy
>
> Thanks for taking the time to reply.
>
> Bob
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