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maudyZ28
November 8th, 2015, 03:33 AM
hi All, been a while since i've posted.

Anyhow. In prep for a turbo build I've got some seimens deka 80lbs in the Ls1 now,
I used the corrected data after searching for a while that was transferred over from the HP tuners files etc.

I have also used the CAX file addition to reduce the hard coded minimum pulse width.

So since changing everything, over (had 42 lb injectors before) it seems that I had to do quite a
bit of modification on the VE table (I run OLSD). The car was (and still is) rich ~12.2 - 13.0 AFR from idle and low throttle <1200 rpm
and was lean on top, running 13.5, but low rpm with no DFCO also runs really rich, like 11 AFR. Previously car was solid in tun at 14.9
normal driving, 12.8 at WOT and overrun with no DFCO was around 13 ish.

So, my question(s)
1) I had to add more fuel up top in the VE, AFR is good at 12.8-12.9 now and I had to remove a lot at low map low rpm for idle etc. So the whole
VE table needed increases and decreases. Is this a result of injector characteristics or the data being a bit off? Shouldn’t the VE have stayed the same?

2) After lowering the VE at the bottom end, it is still rich. But is this (A) the injectors are really hitting the minimal open time, or (B) the low commanded pulse width is adding more fuel ? So I can lower this, as the VE doesnt seem to respond any more?

3) How do I get the overrun with no DFCO to top being so rich, should I really pull the VE super low in the low map area? <30 kpa?

Cheers

statesman
November 8th, 2015, 01:49 PM
Post your tune file.

5.7ute
November 8th, 2015, 02:20 PM
If you are hitting a limit it will be obvious as IBPW will not change as you lower the VE table. Remember that the limit is calculated from the Fuelling portion of the pulsewidth, so the logged value will be higher as this is the total including all modifiers.
A tune and log file will help.

joecar
November 9th, 2015, 04:24 AM
Post tune and log files.

Is your FPR manifold referenced...?

What is your measured rail pressure (measure with reference hose (if referenced) removed)...?

maudyZ28
November 11th, 2015, 06:22 AM
hi all thanks for the replies.

I have no log with the PW to show, I work away so the car is at home and I'd only done 3 rounds of VE to get it running well. Will post the full info when home :) in a few weeks ...