yttz

I'm having major issues getting some RC engineering injectors tuned on my LS6. I'm very close considering the struggle of not having all the needed data. My issue with them now is that upon initial starting of the engine, it runs very lean. After revving it a bit or 30-60 seconds of running it richens up. (going from 17:1 to 13:1 even though command afr leans up around the same time) If you restart the engine after it richens up, it stays that way and all is good. If the engine stays off for more than 15 min or so, the cycle starts over and its lean again. So what table would deal with the initial 30-60 seconds of starting?

flame

iTrader: (13)

Is your wideband warmed up or is the lean reading because it hasn't heated up to give a proper reading? Look into afterstart enrichment if the reading is true.

jimmyblue

iTrader: (11)

AIR pump will make a mess of things, if it's still active.
Misfiring with a cold motor will spoof any oxygen sensor.
Look at what's ramping and what settles in about the
same time as your AFR pops to the right answer, maybe
this is your clue. I'm thinking ECT is driving things, but
that (when cold) ought to push enrichment up. If you
are seeing ECT as the main index of this behavior then
fattening some of the cold columns in the EQ table could
help, but it may also ripple into the starting behavior
and need any fattening, taken back out of the cranking
and afterstart enrichment so you don't double-enrich it.

yttz

I seems that whats happening is the TPS is slowly comming down makeing it get richer and richer. Idle RPM and injector pulse width stay the same, just TPS steps down from 9% to 8% to 7%. What table would change fueling based on TPS at idle with HP tuners? I've yet to find anything. There must be something to smooth keep pulse width in order with TPS...

Also, this is with 2 bar SD tune. No Maf used.

flame

iTrader: (13)

As the throttle closes your manifold vacuum will go up (lower kpa) so it sounds like you need to fine tune the ve table

yttz

It does, but there isn't enough resolution to make proper changes. When it does this its usually its between 33-37kpa which all reference the 35kpa cell according to the histogram. My resolution in that area is 25, 30, 35, 40, 45kpa.

jimmyblue

iTrader: (11)

It should be interpolating and the error from that, only
bad if you have some extreme nonlinearity. What's more
of a problem in my experience, is when you get between
a cell you can hit, and bed in, and one that you can't.
My car won't idle at 30kPa, no way. So you can't get
the data that any automagical tuning scheme wants.
But you have to get it right or the interpolation will be
off.

If you like to work "by eye" then the graphical or split
display modes may be your best bet for massaging the
surface / family of curves. If you're good / lucky at
guessing trajectories, at least you can take a cut at it
and see.

Still unclear to me if this is a commanded, or delivered
fueling problem. It originally seemed thermal, in the
description, and speed density cares a whole lot about
the calculated temperatures.

You might want to look at the same idle speed, cold
and warm, and see whether the MAP*RPM relation to
the airflow g/sec is staying put (it ought to) or moving.
Temperature, calculated somewhat complexly, is the
third leg of that stool. And your fueling drift is either
air mass, or commanded enrichment / trims.

One other thing "in the mix" is injector atomization
and wall boil-off. This is surely temperature dependent.
An injector shot that hits a cold wall will deliver only
part of its mass as useful vapor, the rest comes in
wet and may not burn completely (that's why the
cranking and afterstart enrichment) and incomplete
burn means exhaust oxygen left to fool the wideband.
I couldn't say whether your new injectors differ from
stock in those aspects (cone angle, fineness of fuel
atomization). But it's another hypothesis for your
collection.