Newb: What should I start with first on custom tune (PE, LTFT, MAF, SD, etc)?
06-10-2006, 06:40 PM
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Newb: What should I start with first on custom tune (PE, LTFT, MAF, SD, etc)? I have the latest HPT released. I already have a pretty good Predator tune in my car for the longtubes and cam.
There is so much involved with this program, and I am really limited on time I can spend right now. So in order to maximize my time and getting some good HP out of the car, which parameter should I start with first on the car in tuning. Every how to document goes straight to SD tuning first.
So my main question, which should be my first step to last step in getting full potential from the engine?
There is so much involved with this program, and I am really limited on time I can spend right now. So in order to maximize my time and getting some good HP out of the car, which parameter should I start with first on the car in tuning. Every how to document goes straight to SD tuning first.
So my main question, which should be my first step to last step in getting full potential from the engine?
06-10-2006, 06:59 PM
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The MAF can likely be left alone other than (maybe) the
very low airflow end being bothered by the cam and its
possible inlet pulsation / reversion effects.
The speed density tuning is more about low throttle
and transitional throttle drivability. You can leave it for
later if you like.
If it's the big end you want to tune then it's pretty
much PE table (bearing in mind the open loop fuel
air needs to be somewhat consistent with the PE,
this table is now called EQ Ratio vs MAP vs ECT)
and spark advance. The work to be done is just
finding the sweet spot, or rather the sweet path
(spark and PE changing w/ RPM). The two can be
played off against each other to some extent.
But there is only one optimum.
You want to pick a reasonable delivered AFR and
tighten up the spark against that, avoiding ping
and maximizing some repeatable measure of
performance. It could be track times, dyno results,
a G-Tech or just 40-70 times on an open road.
Whatever is most consistently convenient. You
would like to know what the actual AFR is, and
what you commanded; large errors want MAF,
VE table or fueling models tweaked depending on
what you know about the car & existing tune, or
can deduce from logging. Logging really comes
first, you need to understand what you're
starting with.
You can suck the Predator tune out of the PCM
as your starting point, and it might be educational
to compare the more interesting pieces of it to the
tune files you can find on the repository site (see
sticky?) for cars with a similar cam. Tuners, mail-
order or email-order or in-person, take varying
shortcuts and degrees of care with the details.
Use the compare function and see where your
present tune differs from a stocker, and the ones
you can find for performance modes. That will
highlight the places people end up working over
most, and differences always are about something
(right, or wrong).
very low airflow end being bothered by the cam and its
possible inlet pulsation / reversion effects.
The speed density tuning is more about low throttle
and transitional throttle drivability. You can leave it for
later if you like.
If it's the big end you want to tune then it's pretty
much PE table (bearing in mind the open loop fuel
air needs to be somewhat consistent with the PE,
this table is now called EQ Ratio vs MAP vs ECT)
and spark advance. The work to be done is just
finding the sweet spot, or rather the sweet path
(spark and PE changing w/ RPM). The two can be
played off against each other to some extent.
But there is only one optimum.
You want to pick a reasonable delivered AFR and
tighten up the spark against that, avoiding ping
and maximizing some repeatable measure of
performance. It could be track times, dyno results,
a G-Tech or just 40-70 times on an open road.
Whatever is most consistently convenient. You
would like to know what the actual AFR is, and
what you commanded; large errors want MAF,
VE table or fueling models tweaked depending on
what you know about the car & existing tune, or
can deduce from logging. Logging really comes
first, you need to understand what you're
starting with.
You can suck the Predator tune out of the PCM
as your starting point, and it might be educational
to compare the more interesting pieces of it to the
tune files you can find on the repository site (see
sticky?) for cars with a similar cam. Tuners, mail-
order or email-order or in-person, take varying
shortcuts and degrees of care with the details.
Use the compare function and see where your
present tune differs from a stocker, and the ones
you can find for performance modes. That will
highlight the places people end up working over
most, and differences always are about something
(right, or wrong).
06-11-2006, 02:13 PM
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If I were to the minimum, what should I do first then for tuning.
If I were to do most of everything, like maf and sd tuning what would I do first to last to optimize the tune?
If I were to do most of everything, like maf and sd tuning what would I do first to last to optimize the tune?
