Hi all.
A little update & reply to you all.



kur4o
I got a little confused what you are trying to do.

First you need that fuel flow figured. If you have the fuel flow at 42 pounds at 4 bar, you need to convert it to 3 bar flow.

The formula is x*0.86602540378
x= fuel flow at zero vacuum at 4 bar fuel pressure, [zero vacuum value should be the lowest value in the ls data].

Than you have to convert the voltage offset. You should have a ls data table called injector offset vs vacuum vs volts .
Take again the row at zero vacuum and interpolate to lt1 voltage . It will take some time but it can be done by hand easily.
The injectors are rated 42lb at 3 bar (50 at 4 bar).
I understood we used the fuel pressure (which is measured from above atomspheric).
So I had _measured_ fuel pressure at 47psi and used the 324.05kPa figures accordingly, not 300kPa (3bar) like I have now, see below.


spfautsch
that was measured fuel pressure.With a factory pressure regulator?
All measurements are slightly more accurate guesses, gotta start somewhere.

sherlock9c1
For what it's worth, on every older LT1 I've measured, the fuel pressure has always been on the high side, usually 3-4psi higher than spec.
spfautsch
For what it's worth, I doubt you (or, more specifically Terminal_Crazy) was / were measuring with a recently calibrated, laboratory grade instrument.
One can easily spend $300-$400 on such a device and it may still be off 1-3 psi "out of the box".

My point is that I'm not sure I would skew all my injector data based on measurements taken with a $20-$50 instrument.
And bear in mind a fuel injector "test kit" that sells for $50 likely includes a gauge that's worth about $5 and cost about $2.
Just my $0.02, for what it's worth (considerably less than $0.02).
Whilst I don't disagree with you, Not measuring it is no less a guess.
The 47psi value converted to 324.053kPa
I interpolated & used the data from 324.05_ so already ANY data is skewed.
Enough to make a difference... unlikely.

....
Anyway
I reset the IFR to the rated 42lb
Recalculated the Voltage Offsets to the 300kPa figure
again Nothing quite matches the same with the generic data or the supplied data
The values were slightly lower ( 1 maybe 2 hex values in each cell).
NOTE: I suspect the VE table has a finer adjustment than the Voltage offsets themselves.

By the time i'd dicked about with the VE table I'm pretty much back where I was before.

I spent the weekend jacking tables around, anything air flow/mass related.
The BLM's & VE were extremely rich
I had the car running real nice, no surge BUT the O2's were averaging 500mV and the car stunk of fuel.
Idle AFR was showing 14.5-15.5 and the fuel guage was moving faster than I was.

I pulled the O2 thresholds to get the O2's averaging 450mV and sloped the VE Tables and voila, I'm back where I was again.


I think I'll tidy the VE tables back up and try with the MAF.
I also have another PCM (1995) rather than a 1997. Doubt that should be an issue?
And some fresh O2 sensors.

Mitch