Lean out A/F on Hp tuners
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From: Ft Lauderdale, FL
Lean out A/F on Hp tuners I have HP tuners and I want to lean out my A/F ratio It is currently around 12.2:1 and im looking closer to 13.0:1 What tables do I go to and what do I do? Please dont abreviate because I am very new and wont even understand. thanks
You need to bring down the PE value, but behind that
is the open loop fuel air (or EQ ratio) vs ECT vs MAP
which also may need to be skinnied down.
Figure your fuel air multiplier, first cut, as 14.7/desired
AFR. If you really want 13.0:1 then use a 1.131 value.
However your indicated reading (12.2:1) is not all that
consistent with the stock PE values I see in my tune so
you may suspect some other airflow or fuel delivery
model errors are present; you will have to cut-and-try.
If you want to try the minimum scale your PE table by
(12.2/13.0)=0.938, and make sure the OLFA at high
MAP is no greater, and get the wideband on it again.
You really would like to observe mixture across the
RPM band, the PE profile may want some tapering
to comp out fuel fade or other stacked up errors that
vary with RPM. The OLFA table is a second degree of
freedom, sort of. Set OLFA to whatever makes the
minimum FAM, maximum AFR work out and then use
PE wherever you need some "upside". Richest one
wins.
is the open loop fuel air (or EQ ratio) vs ECT vs MAP
which also may need to be skinnied down.
Figure your fuel air multiplier, first cut, as 14.7/desired
AFR. If you really want 13.0:1 then use a 1.131 value.
However your indicated reading (12.2:1) is not all that
consistent with the stock PE values I see in my tune so
you may suspect some other airflow or fuel delivery
model errors are present; you will have to cut-and-try.
If you want to try the minimum scale your PE table by
(12.2/13.0)=0.938, and make sure the OLFA at high
MAP is no greater, and get the wideband on it again.
You really would like to observe mixture across the
RPM band, the PE profile may want some tapering
to comp out fuel fade or other stacked up errors that
vary with RPM. The OLFA table is a second degree of
freedom, sort of. Set OLFA to whatever makes the
minimum FAM, maximum AFR work out and then use
PE wherever you need some "upside". Richest one
wins.
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Joined: Oct 2005
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From: Taxme, Ohio
Originally Posted by jimmyblue
You need to bring down the PE value, but behind that
is the open loop fuel air (or EQ ratio) vs ECT vs MAP
which also may need to be skinnied down.
is the open loop fuel air (or EQ ratio) vs ECT vs MAP
which also may need to be skinnied down.
Sorry to butt in 1999transamws6....
Originally Posted by 01Z28M6
I will create a new thread but in the mean time, I'm on the other side of this question. I had my car dyno'd with an air/fuel ratio analysis. I'm lean (14:1) and need to bring it down. I did not know there was any way to do this with a hpp tune. I was looking at the Granatelli programmable maf sensor.
Sorry to butt in 1999transamws6....
Sorry to butt in 1999transamws6....
buggered the MAF or fueling somehow. I would be suspicious
of the AFR "analysis". Especially if the probe was up the tailpipe.
That is very easy to screw up, it needs to be in there past the
furthest-in reach of fresh air reversion. I recently saw a car
that came with a dyno sheet showing 14-15:1 WOT AFR but
-my- wideband, put to a header O2 bung, showed low 12:1s.
I would not trust this result although it -could- happen, like
if you already had one of the "performance improving" MAFs
from GMS or early-years SLP/Pace, or simply had 5 years'
worth of K&N spooge all over the sense elements.
Next, having a "programmable" MAF is a one-trick pony and
you still need the feedback (hopefully more trustworthy) to dial
it in. For the retail price, you're over halfway to real and
comprehensive tuning ability. Closer, if you happen to find a
right-license used copy.
HPP3 will not fix this for you. Some handhelds will adjust it
"some". But again these are limited devices with a price tag
out of proportion to their capability.
