Comments from reviewing the "Tuning Document"
05-24-2005, 10:12 AM
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Comments from reviewing the "Tuning Document" Somebody asked me,
I hadn't, but I just did, and here are my comments
relative to my own experiences / preferences. I
hope this will be useful "fertilizer" to help it grow.
It's criticism meant in the constructive sense, and
based on a real-time read of the document as is.
In general it's a good piece of work, with which I
have detailed differences of opinion.
----------------------------------------------------
I have approached tuning my car from a very different
direction; more event / dislike-driven than a tuning
plan.
I disagree with eliminating torque management. It has
a definite purpose and benefit. However, eliminating
it is much simpler than training it to play nice. The
sheer number of people having to move up to their
second, third rebuilt trans argues against trans TM
deletion.
I also haven't had enough trouble from my MAF to
warrant jumping on the speed-density tuning train.
I have tweaked on my VE table to improve idle and
low RPM fuel trimming, when I discovered the MAF
table had no effect there and was having tip-in KR
that was out of line with steady state spark advance
tolerance. This was before SD tuning "caught fire" on
the 'boards. It becomes more appropriate / necessary
when you go to big cam or just want to strip stuff
out of the engine compartment and air tract. But I
think for someone with low mods it may be just a
detour down the scenic route. But it probaby needs to
be gone through at least once when you put cam,
headers, even a grossly improved cat-back on. I did
not go through the full drill as described; I just tweak
and smooth and observe, repetitively.
However I did work a remote tune by email with a guy
off this 'board and I did have him run through a more
methodical drill. I did not disable the MAF at the time,
just turned off his closed loop in a "diagnostic tune",
had him run logging sessions and observed the O2
readings to work the low end of the VE table over in
a binary search sort of way. The big end I just worked
over by eye and by KR events / O2 dips on throttle.
But this is something I'm used to doing, just in a
different field, and probably the enthusiast tuner can
use more of a cookbook. I'm a pinch and dash sort,
myself.
I disagree that -5 to +5 is good for LTFTs. No LTFT
above zero, is my view. The purpose is to not have
any "mystery adders" to WOT fueling. A +5 LTFT will
show up as a 5% rich error, like 13:1 becomes 12.4:1;
you're trying to tune it tighter than that. On the flip
side there is nothing, really, wrong with negative trims
and I prefer this bias for other reasons as well, on an
A4; elevating the airflow back-door elevates the
"load" and trans line pressures etc. This is why I run
the fattest of the factory MAF tables with my 85mm.
The only place where trimmed-lean, naturally-rich
might bother you is on transient throttle and there
a little enrichment is more likely a bonus.
Knock Retard with stock settings messes up your
attempts to eliminate it by the histogram method.
It's too persistent once triggerd and will splash over
onto adjacent cells as you drag the tail through them
in time. I have reduced my KR attack rate and taken
the decay rate way up which clarifies this some. But
you can't really get rid of the effect entirely. Still if
you pursue the method in the doc you will be taking
timing out of cells that don't really need it, and then
spend more time tweaking them back up. You really
want to first see the root of the knock event. This is
something I prefer to do in Excel where I can see at a
glance the knock event and its predecessors. In my
experience all of my KR, with factory spark or even
Predator-level advance (+6 degrees) has been from
fueling shortfall on throttle opening. This is seen as a
dip in the O2 voltage in the prior 1-3 frames. If you
correct this (most likely it's the VE table, unsteady
MAP follows throttle opening and puts you into SD
mode for some chunk of time) then transient KR will
be suppressed and you can maximize timing for what
the engine can take in steady pulling. But if you have
transient KR and stock settings the KR will persist for
many seconds and obscure the real timing tolerance.
PE section makes no mention of the PE MAP enable or
TPS enable fields. These are something that can be
worth playing with, some people suffer from late PE
apply, a ping that comes in at (say) roughly half
throttle, mid-MAP. This is a street driving sweet spot
(but maybe sour). Lowering PE enable values may be
helpful though too much, and you may see a drop in
mileage without performance benefit.
Transmission settings area I see (surprise) some stuff
to disagree with as well. The shift speed vs TPS%
table which it says to leave alone, is the one that is
key to around-town responsiveness and powerband
management at less than full throttle, getting a pedal
responsive shift action is major fahrvergnugen. I have
posted a few Excel sheets (from now-obsolete tunes
but still useful as a guide) with shiftpoint settings.
Shifting points, pressures (cycle times and hardness)
are very setup- and taste-dependent.
Personally I would prefer to see a document that is
written more from the symptom -> treatment point
of view, than one that encourages a routine series
of tuning activities. Not to disparage the work, which
represents a good bit of effort and initiative and is the
most useful reference I've seen; just that I see some
people go plunging ahead into things they didn't seem
to really need to mess with. Like people with stock
config cars jumping into speed density tuning, etc.
because it was the second thing on the list.
I think there's too little emphasis on figuring out what
the car wants, as a predecessor to tuning action. The
diagnosis should come before the prescription. Though
we can all agree she needs to get her fat *** on the
Stairmaster
relative to my own experiences / preferences. I
hope this will be useful "fertilizer" to help it grow.
It's criticism meant in the constructive sense, and
based on a real-time read of the document as is.
In general it's a good piece of work, with which I
have detailed differences of opinion.
----------------------------------------------------
I have approached tuning my car from a very different
direction; more event / dislike-driven than a tuning
plan.
I disagree with eliminating torque management. It has
a definite purpose and benefit. However, eliminating
it is much simpler than training it to play nice. The
sheer number of people having to move up to their
second, third rebuilt trans argues against trans TM
deletion.
I also haven't had enough trouble from my MAF to
warrant jumping on the speed-density tuning train.
I have tweaked on my VE table to improve idle and
low RPM fuel trimming, when I discovered the MAF
table had no effect there and was having tip-in KR
that was out of line with steady state spark advance
tolerance. This was before SD tuning "caught fire" on
the 'boards. It becomes more appropriate / necessary
when you go to big cam or just want to strip stuff
out of the engine compartment and air tract. But I
think for someone with low mods it may be just a
detour down the scenic route. But it probaby needs to
be gone through at least once when you put cam,
headers, even a grossly improved cat-back on. I did
not go through the full drill as described; I just tweak
and smooth and observe, repetitively.
However I did work a remote tune by email with a guy
off this 'board and I did have him run through a more
methodical drill. I did not disable the MAF at the time,
just turned off his closed loop in a "diagnostic tune",
had him run logging sessions and observed the O2
readings to work the low end of the VE table over in
a binary search sort of way. The big end I just worked
over by eye and by KR events / O2 dips on throttle.
But this is something I'm used to doing, just in a
different field, and probably the enthusiast tuner can
use more of a cookbook. I'm a pinch and dash sort,
myself.
I disagree that -5 to +5 is good for LTFTs. No LTFT
above zero, is my view. The purpose is to not have
any "mystery adders" to WOT fueling. A +5 LTFT will
show up as a 5% rich error, like 13:1 becomes 12.4:1;
you're trying to tune it tighter than that. On the flip
side there is nothing, really, wrong with negative trims
and I prefer this bias for other reasons as well, on an
A4; elevating the airflow back-door elevates the
"load" and trans line pressures etc. This is why I run
the fattest of the factory MAF tables with my 85mm.
The only place where trimmed-lean, naturally-rich
might bother you is on transient throttle and there
a little enrichment is more likely a bonus.
Knock Retard with stock settings messes up your
attempts to eliminate it by the histogram method.
It's too persistent once triggerd and will splash over
onto adjacent cells as you drag the tail through them
in time. I have reduced my KR attack rate and taken
the decay rate way up which clarifies this some. But
you can't really get rid of the effect entirely. Still if
you pursue the method in the doc you will be taking
timing out of cells that don't really need it, and then
spend more time tweaking them back up. You really
want to first see the root of the knock event. This is
something I prefer to do in Excel where I can see at a
glance the knock event and its predecessors. In my
experience all of my KR, with factory spark or even
Predator-level advance (+6 degrees) has been from
fueling shortfall on throttle opening. This is seen as a
dip in the O2 voltage in the prior 1-3 frames. If you
correct this (most likely it's the VE table, unsteady
MAP follows throttle opening and puts you into SD
mode for some chunk of time) then transient KR will
be suppressed and you can maximize timing for what
the engine can take in steady pulling. But if you have
transient KR and stock settings the KR will persist for
many seconds and obscure the real timing tolerance.
PE section makes no mention of the PE MAP enable or
TPS enable fields. These are something that can be
worth playing with, some people suffer from late PE
apply, a ping that comes in at (say) roughly half
throttle, mid-MAP. This is a street driving sweet spot
(but maybe sour). Lowering PE enable values may be
helpful though too much, and you may see a drop in
mileage without performance benefit.
Transmission settings area I see (surprise) some stuff
to disagree with as well. The shift speed vs TPS%
table which it says to leave alone, is the one that is
key to around-town responsiveness and powerband
management at less than full throttle, getting a pedal
responsive shift action is major fahrvergnugen. I have
posted a few Excel sheets (from now-obsolete tunes
but still useful as a guide) with shiftpoint settings.
Shifting points, pressures (cycle times and hardness)
are very setup- and taste-dependent.
Personally I would prefer to see a document that is
written more from the symptom -> treatment point
of view, than one that encourages a routine series
of tuning activities. Not to disparage the work, which
represents a good bit of effort and initiative and is the
most useful reference I've seen; just that I see some
people go plunging ahead into things they didn't seem
to really need to mess with. Like people with stock
config cars jumping into speed density tuning, etc.
because it was the second thing on the list.
I think there's too little emphasis on figuring out what
the car wants, as a predecessor to tuning action. The
diagnosis should come before the prescription. Though
we can all agree she needs to get her fat *** on the
Stairmaster
05-24-2005, 11:51 AM
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I dont like the SD tuning either. Maybe i will have to go to it later but as of now I have everything in place w/o it.
Rather than a what to do.. I would love to see a this is what this table does and if you do this it in return doest this..... (kinda like the teach them to fish)
I have searched and its really hard to find out what some of the tables actually do... I know what most of the main tables do now but I didnt coming into tuning as a complete newb.
Rather than a what to do.. I would love to see a this is what this table does and if you do this it in return doest this..... (kinda like the teach them to fish)
I have searched and its really hard to find out what some of the tables actually do... I know what most of the main tables do now but I didnt coming into tuning as a complete newb.
05-24-2005, 12:16 PM
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This is along the same lines of thought I had when contemplating a MAF recalibration. If we alter the airflow characteristics of the motor by adding ram air kits, high flow lids, and free-flowing exhausts, then it is a theory that the MAF readings will be inconsistent with the true dynamic airflow of the motor. It makes sense to me that this would occur as we are dealing with some rather complicated equations that aren't exactly linear, which means a simple scaling of the tables will only help fix one area. However, going through the whole SD process seems to be overkill on a car like mine where the internals are still stock. I would think recalibrating the MAF to get it inline with the true DAF would be enough before I started tweaking the VE table without going into SD mode. Unfortunately, I don't recall anyone responding with a clear answer as to why this would or wouldn't work. I've yet to dive into the HPTuners world because of issues like this, which I consider to be rather significant considering my limited knowledge of what boils down to the cause and effect statement made above. That's what should be in the help files...and in "English." This table controls blah, blah, blah. The values have a ______ relationship. Increasing the values results in blah, blah, blah. Decreasing the values.... Just my $.02.
05-24-2005, 02:15 PM
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Not to beat a dead horse....Torque Management.......I just set mine to zero and I have minimal mods (LTs, lid, LS6 intake, stock converter)........am I really in danger of killing the tranny? If so....what do I need to do to keep it safe? Should I reset TM or just back it off a little?
As for the tranny...for anyone that has and A4 you must do this.......I changed my shift points and this makes the car feel like it's much more responsive. A definite must-do. I also changed the speed of the actual gear switching. I didn't go too radical (.200 at the right side) but I feel a huge difference at WOT shifts.
As for the tranny...for anyone that has and A4 you must do this.......I changed my shift points and this makes the car feel like it's much more responsive. A definite must-do. I also changed the speed of the actual gear switching. I didn't go too radical (.200 at the right side) but I feel a huge difference at WOT shifts.
05-24-2005, 08:18 PM
#5
Originally Posted by jimmyblue
Somebody asked me,
I hadn't, but I just did, and here are my comments
relative to my own experiences / preferences. I
hope this will be useful "fertilizer" to help it grow.
It's criticism meant in the constructive sense, and
based on a real-time read of the document as is.
In general it's a good piece of work, with which I
have detailed differences of opinion.
----------------------------------------------------
I have approached tuning my car from a very different
direction; more event / dislike-driven than a tuning
plan.
I disagree with eliminating torque management. It has
a definite purpose and benefit. However, eliminating
it is much simpler than training it to play nice. The
sheer number of people having to move up to their
second, third rebuilt trans argues against trans TM
deletion.
I also haven't had enough trouble from my MAF to
warrant jumping on the speed-density tuning train.
I have tweaked on my VE table to improve idle and
low RPM fuel trimming, when I discovered the MAF
table had no effect there and was having tip-in KR
that was out of line with steady state spark advance
tolerance. This was before SD tuning "caught fire" on
the 'boards. It becomes more appropriate / necessary
when you go to big cam or just want to strip stuff
out of the engine compartment and air tract. But I
think for someone with low mods it may be just a
detour down the scenic route. But it probaby needs to
be gone through at least once when you put cam,
headers, even a grossly improved cat-back on. I did
not go through the full drill as described; I just tweak
and smooth and observe, repetitively.
However I did work a remote tune by email with a guy
off this 'board and I did have him run through a more
methodical drill. I did not disable the MAF at the time,
just turned off his closed loop in a "diagnostic tune",
had him run logging sessions and observed the O2
readings to work the low end of the VE table over in
a binary search sort of way. The big end I just worked
over by eye and by KR events / O2 dips on throttle.
But this is something I'm used to doing, just in a
different field, and probably the enthusiast tuner can
use more of a cookbook. I'm a pinch and dash sort,
myself.
I disagree that -5 to +5 is good for LTFTs. No LTFT
above zero, is my view. The purpose is to not have
any "mystery adders" to WOT fueling. A +5 LTFT will
show up as a 5% rich error, like 13:1 becomes 12.4:1;
you're trying to tune it tighter than that. On the flip
side there is nothing, really, wrong with negative trims
and I prefer this bias for other reasons as well, on an
A4; elevating the airflow back-door elevates the
"load" and trans line pressures etc. This is why I run
the fattest of the factory MAF tables with my 85mm.
The only place where trimmed-lean, naturally-rich
might bother you is on transient throttle and there
a little enrichment is more likely a bonus.
Knock Retard with stock settings messes up your
attempts to eliminate it by the histogram method.
It's too persistent once triggerd and will splash over
onto adjacent cells as you drag the tail through them
in time. I have reduced my KR attack rate and taken
the decay rate way up which clarifies this some. But
you can't really get rid of the effect entirely. Still if
you pursue the method in the doc you will be taking
timing out of cells that don't really need it, and then
spend more time tweaking them back up. You really
want to first see the root of the knock event. This is
something I prefer to do in Excel where I can see at a
glance the knock event and its predecessors. In my
experience all of my KR, with factory spark or even
Predator-level advance (+6 degrees) has been from
fueling shortfall on throttle opening. This is seen as a
dip in the O2 voltage in the prior 1-3 frames. If you
correct this (most likely it's the VE table, unsteady
MAP follows throttle opening and puts you into SD
mode for some chunk of time) then transient KR will
be suppressed and you can maximize timing for what
the engine can take in steady pulling. But if you have
transient KR and stock settings the KR will persist for
many seconds and obscure the real timing tolerance.
PE section makes no mention of the PE MAP enable or
TPS enable fields. These are something that can be
worth playing with, some people suffer from late PE
apply, a ping that comes in at (say) roughly half
throttle, mid-MAP. This is a street driving sweet spot
(but maybe sour). Lowering PE enable values may be
helpful though too much, and you may see a drop in
mileage without performance benefit.
Transmission settings area I see (surprise) some stuff
to disagree with as well. The shift speed vs TPS%
table which it says to leave alone, is the one that is
key to around-town responsiveness and powerband
management at less than full throttle, getting a pedal
responsive shift action is major fahrvergnugen. I have
posted a few Excel sheets (from now-obsolete tunes
but still useful as a guide) with shiftpoint settings.
Shifting points, pressures (cycle times and hardness)
are very setup- and taste-dependent.
Personally I would prefer to see a document that is
written more from the symptom -> treatment point
of view, than one that encourages a routine series
of tuning activities. Not to disparage the work, which
represents a good bit of effort and initiative and is the
most useful reference I've seen; just that I see some
people go plunging ahead into things they didn't seem
to really need to mess with. Like people with stock
config cars jumping into speed density tuning, etc.
because it was the second thing on the list.
I think there's too little emphasis on figuring out what
the car wants, as a predecessor to tuning action. The
diagnosis should come before the prescription. Though
we can all agree she needs to get her fat *** on the
Stairmaster
I hadn't, but I just did, and here are my comments
relative to my own experiences / preferences. I
hope this will be useful "fertilizer" to help it grow.
It's criticism meant in the constructive sense, and
based on a real-time read of the document as is.
In general it's a good piece of work, with which I
have detailed differences of opinion.
----------------------------------------------------
I have approached tuning my car from a very different
direction; more event / dislike-driven than a tuning
plan.
I disagree with eliminating torque management. It has
a definite purpose and benefit. However, eliminating
it is much simpler than training it to play nice. The
sheer number of people having to move up to their
second, third rebuilt trans argues against trans TM
deletion.
I also haven't had enough trouble from my MAF to
warrant jumping on the speed-density tuning train.
I have tweaked on my VE table to improve idle and
low RPM fuel trimming, when I discovered the MAF
table had no effect there and was having tip-in KR
that was out of line with steady state spark advance
tolerance. This was before SD tuning "caught fire" on
the 'boards. It becomes more appropriate / necessary
when you go to big cam or just want to strip stuff
out of the engine compartment and air tract. But I
think for someone with low mods it may be just a
detour down the scenic route. But it probaby needs to
be gone through at least once when you put cam,
headers, even a grossly improved cat-back on. I did
not go through the full drill as described; I just tweak
and smooth and observe, repetitively.
However I did work a remote tune by email with a guy
off this 'board and I did have him run through a more
methodical drill. I did not disable the MAF at the time,
just turned off his closed loop in a "diagnostic tune",
had him run logging sessions and observed the O2
readings to work the low end of the VE table over in
a binary search sort of way. The big end I just worked
over by eye and by KR events / O2 dips on throttle.
But this is something I'm used to doing, just in a
different field, and probably the enthusiast tuner can
use more of a cookbook. I'm a pinch and dash sort,
myself.
I disagree that -5 to +5 is good for LTFTs. No LTFT
above zero, is my view. The purpose is to not have
any "mystery adders" to WOT fueling. A +5 LTFT will
show up as a 5% rich error, like 13:1 becomes 12.4:1;
you're trying to tune it tighter than that. On the flip
side there is nothing, really, wrong with negative trims
and I prefer this bias for other reasons as well, on an
A4; elevating the airflow back-door elevates the
"load" and trans line pressures etc. This is why I run
the fattest of the factory MAF tables with my 85mm.
The only place where trimmed-lean, naturally-rich
might bother you is on transient throttle and there
a little enrichment is more likely a bonus.
Knock Retard with stock settings messes up your
attempts to eliminate it by the histogram method.
It's too persistent once triggerd and will splash over
onto adjacent cells as you drag the tail through them
in time. I have reduced my KR attack rate and taken
the decay rate way up which clarifies this some. But
you can't really get rid of the effect entirely. Still if
you pursue the method in the doc you will be taking
timing out of cells that don't really need it, and then
spend more time tweaking them back up. You really
want to first see the root of the knock event. This is
something I prefer to do in Excel where I can see at a
glance the knock event and its predecessors. In my
experience all of my KR, with factory spark or even
Predator-level advance (+6 degrees) has been from
fueling shortfall on throttle opening. This is seen as a
dip in the O2 voltage in the prior 1-3 frames. If you
correct this (most likely it's the VE table, unsteady
MAP follows throttle opening and puts you into SD
mode for some chunk of time) then transient KR will
be suppressed and you can maximize timing for what
the engine can take in steady pulling. But if you have
transient KR and stock settings the KR will persist for
many seconds and obscure the real timing tolerance.
PE section makes no mention of the PE MAP enable or
TPS enable fields. These are something that can be
worth playing with, some people suffer from late PE
apply, a ping that comes in at (say) roughly half
throttle, mid-MAP. This is a street driving sweet spot
(but maybe sour). Lowering PE enable values may be
helpful though too much, and you may see a drop in
mileage without performance benefit.
Transmission settings area I see (surprise) some stuff
to disagree with as well. The shift speed vs TPS%
table which it says to leave alone, is the one that is
key to around-town responsiveness and powerband
management at less than full throttle, getting a pedal
responsive shift action is major fahrvergnugen. I have
posted a few Excel sheets (from now-obsolete tunes
but still useful as a guide) with shiftpoint settings.
Shifting points, pressures (cycle times and hardness)
are very setup- and taste-dependent.
Personally I would prefer to see a document that is
written more from the symptom -> treatment point
of view, than one that encourages a routine series
of tuning activities. Not to disparage the work, which
represents a good bit of effort and initiative and is the
most useful reference I've seen; just that I see some
people go plunging ahead into things they didn't seem
to really need to mess with. Like people with stock
config cars jumping into speed density tuning, etc.
because it was the second thing on the list.
I think there's too little emphasis on figuring out what
the car wants, as a predecessor to tuning action. The
diagnosis should come before the prescription. Though
we can all agree she needs to get her fat *** on the
Stairmaster
I've been working on an update with better information and images for some time. I've thrown away so many revisions it's crazy. I suppose I'll get there sooner than later.
I have thought about the cause > effect approach and will use. Thanks for the input!