Tuning VE open loop - really high values?

Hey all, I've been working on getting my Typhoon LSx swap to idle and had a question. I'm not where I can post a tune yet (don't have my laptop here), but this is a question in general.

First, my details:

LQ4 motor, stock internals
LS6 intake
60# Siemens injectors
2 Bar SD converted OS (done as per the instructional video)
58psi fuel pressure
No MAF installed, Syclone IAT sensor installed.

Here is the process I went through to get where I'm at:
Loaded stock LQ4 tune
Turned off VATS, EGR, rear O2's
Failed out the MAF (zero'ed the table, MAF set to 0Hz, high disable to 12800rpm, DTC's set to Mil on First)
Put in new values for injectors based on the Excel spreadsheet.

At this point I figured I'd try to get it running. From what I've read, since I don't have a cam, it shouldn't be too much to get it idling. Perhaps the intake swap will throw it off a bit, but I had some interesting results.

When I started the truck, I had to give it throttle to get it started. If I went below 6% throttle, it died. If I forced closed loop, I could get down to 2%, but any lower, it would die.

I hooked up the PLX WBO2, and found that in closed loop, I was hitting my targeted afr, but in open loop, I was up around 19 :bigshock:

I double checked my FP when running, it was at 58, no problem. I checked for vacuum leaks, no problem. So I decided to start messing with the VE tables in open loop to see if I could get it to change.

What I ended up with was drastically higher values in my VE table around idle RPM's/kPa, like nearly double what they were.

The general question is:

Should my values change THAT much when I'm only running an intake and injectors? I'm only working on idle at this point.

Thanks in advance.

post before and after tune....

Yea what values are you getting?

should'nt be double. the minute you post both tunes and a scan you will get instant help.

Ok I'll post a tune when I have access to the laptop.

I remember specifically around 1200rpm, 25-30kPa:

The original value was 55'ish, and I ended up at 90'ish, this was after I did a full 1.5 multiply on the table originally. The stock value was around the 40 in that range.

I'm just wondering if that much of a change is normal.

Thanks for the quick replies.

What mods do you have?

Quote:

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Originally Posted by Ben Charles

What mods do you have?

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I've listed everything above, but basically it's an LQ4 with an LS6 intake, 60lb injectors. I am running a turbo, but it's not even hooked into the intake yet.

Without the tune file or the vehicle in front of us we can only guess ... my guess would be that the data for the injectors (that you put in) are suspect or a vacuum leak.

Either injector data is wrong or you don't have the maf failed.

Thanks for the help everyone. I realized that I had loaded an old tune, that had bad injector data in it. Now it's idling, minor changes to the VE table, and it even idles great in closed loop.

Thanks everyone for the tips.