easy !!! where to start
07-11-2006, 01:59 AM
#1
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easy !!! where to start ok after some reading im a little confused on where to start tuneing
as of now i have a ok tune that pretty close but i do know i need a little ilde tuneing, my maf table is a little off, finally my car is running lean at wot and rich at part throddle
should i first get raf corrected? my VE table ? my maf table?
i know the answer is out there but after reading a bit im kinda confsed...
as of now i have a ok tune that pretty close but i do know i need a little ilde tuneing, my maf table is a little off, finally my car is running lean at wot and rich at part throddle
should i first get raf corrected? my VE table ? my maf table?
i know the answer is out there but after reading a bit im kinda confsed...
07-11-2006, 03:44 PM
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If I Had To Gess I Would Say Ve Table Since This Is Done In Sd Mode.. Then Calibrate The Maf To Re-algin Fueltrims With The Maf On .. But When Do You Do The Raf? And Pe
07-11-2006, 06:01 PM
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Running airflow required, is going to depend a lot on
the mixture you've got. Old school, you used to turn
the idle air screw until you got the maximum vacuum
(this being the sign of motor mixture happiness). Now
you just want to adjust VE until idle open loop mixture
is centered up, then move up to the low pedal, non-
enriched and get that range of RPM, MAP clean too.
With the lumpy-lump cam you have to factor out the
high idle MAP, potential enrichment of idle from the
open loop fuel air table. You may have to create a
special "tuning tune" to make it stay put at 1.000
and then you can use the in-car O2s as your "decision
flag" and search your way to the truth.
Most of the SD tuning methods want you to align the
MAF to whatever resulted. But my opinion is, a Delphi
MAF is probably more trustworthy than any human
calibration activity. MAF only has to tell you about air.
Speed density tuning, using O2 sensor feedback, has
all fuel errors embedded in the result. So going back
to your fuel pressure logging question, that really is
a good thing to have a grasp of, and work into your
IFR table values before you get all happy with VE
tweaking. Similarly whatever you can dig up for sensible
injector offsets (good luck) will have a large effect on
the idle fueling and the idle-range VE table you end up
with - probably making you then mistrust the MAF and
bend it all up to fit the pack of lies from the fuel side.
All we have in there now is a standard IFR table for
the nominal injector rating and an assumed 58PSI rail.
Be good to have an idle, cruise, half-throttle and WOT-
upshift pressure readings to beat against that.
I'd stick with the PE we put in there (12.7:1-ish) until
you have an airflow setup that's staying put.
the mixture you've got. Old school, you used to turn
the idle air screw until you got the maximum vacuum
(this being the sign of motor mixture happiness). Now
you just want to adjust VE until idle open loop mixture
is centered up, then move up to the low pedal, non-
enriched and get that range of RPM, MAP clean too.
With the lumpy-lump cam you have to factor out the
high idle MAP, potential enrichment of idle from the
open loop fuel air table. You may have to create a
special "tuning tune" to make it stay put at 1.000
and then you can use the in-car O2s as your "decision
flag" and search your way to the truth.
Most of the SD tuning methods want you to align the
MAF to whatever resulted. But my opinion is, a Delphi
MAF is probably more trustworthy than any human
calibration activity. MAF only has to tell you about air.
Speed density tuning, using O2 sensor feedback, has
all fuel errors embedded in the result. So going back
to your fuel pressure logging question, that really is
a good thing to have a grasp of, and work into your
IFR table values before you get all happy with VE
tweaking. Similarly whatever you can dig up for sensible
injector offsets (good luck) will have a large effect on
the idle fueling and the idle-range VE table you end up
with - probably making you then mistrust the MAF and
bend it all up to fit the pack of lies from the fuel side.
All we have in there now is a standard IFR table for
the nominal injector rating and an assumed 58PSI rail.
Be good to have an idle, cruise, half-throttle and WOT-
upshift pressure readings to beat against that.
I'd stick with the PE we put in there (12.7:1-ish) until
you have an airflow setup that's staying put.
07-11-2006, 08:29 PM
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I HAVE A CUST IFR TABLE CURETSY OF TSP MAIL ORDER TUNIENG
OVER ALL THE CAR TRIMED RICH IN CLOSED LOOP BUT HAD A GOOD AFR @ WOT BUT AFTER DESCREENING THE MAF MY WOT IS LEAN AND MY CLOSED LOOP IS MORE IRRATIC
today i loged drove about 1.5 rs in sd mode and im gonna log my trims tommrow i figure why not just correct the ve table (even though its not far off) and i guess ll just have to adjust my pe multipluiers to bring my wot afr back down... as for the maf i am pretty sure i need a recalibration i noticed my part throddle afr is much less irratic when in sd mode so im guessing my descreening really ddint sit well with my current maf table
OVER ALL THE CAR TRIMED RICH IN CLOSED LOOP BUT HAD A GOOD AFR @ WOT BUT AFTER DESCREENING THE MAF MY WOT IS LEAN AND MY CLOSED LOOP IS MORE IRRATIC
today i loged drove about 1.5 rs in sd mode and im gonna log my trims tommrow i figure why not just correct the ve table (even though its not far off) and i guess ll just have to adjust my pe multipluiers to bring my wot afr back down... as for the maf i am pretty sure i need a recalibration i noticed my part throddle afr is much less irratic when in sd mode so im guessing my descreening really ddint sit well with my current maf table