Hello all,
I've been working to iron out my tune, and I've been struggling with what I think is a rich idle. The WB shows around 13.2-14.7 but the car smells rich. I've adjusted the MAF tables to get it as happy as possible, but I'm wondering if I should mess with Offset Compensation versus Battery Voltage.

I'm running 280 155 931 (98 LS1 injectors) at 43 psi on a $6E ARAP and have the stock injector offset comp vs bat voltage values in there.

I've found values for SVO and other type of Bosch III injectors but not these particular ones.
Am I going in the wrong direction to address the idle issue? I read Bosch III flow more fuel than stock at low PW.

Thanks in advance!!

 

Does anyone have the offset compensation vs battery voltage for the 28lb LS1 injectors?

 

Not an offset summary, but maybe this guy is onto something.
http://ls1tech.com/forums/fueling-in...155-931-a.html

 

Thanks Abubaca. I'll look into that as well.


I originally came across this post that got me thinking about messing with the PW offset in the first place.
https://www.thirdgen.org/forums/diy-...gn-iii-pw.html

Specifically this post from RBob...

From what I've found on the 'net the 280-155-700 injector is a 19#/hr. But that is with a substitute liquid (not gasoline).

I'm not sure if I used the correct data sheet. As the 280-155-700 is a Bosch number which Ford doesn't use. I used the Ford 19 #/hr data.

With that here is the data for the injector at 44 psi, values in mSec:

6.4 V: 3.07851247
8.0 V: 1.85340073
9.6 V: 1.30766195
11.2 V: 0.99121428
12.8 V: 0.76537403
14.4 V: 0.60906068
15.0 V: 0.55248610*

Can round as required and extrapolate from the 14.4 V and 15 V for the 16 V entry.

Minimum PW is: 0.853 mSec

RBob.

 

Yeah...some people speak that language everyday. For me, it was a steep learning curve, but I managed to get a grip on it, and have all the Ford numbers for my 30 pounders converted over to my ECM/tune numbers, and honestly, if you asked me to explain it all again.....ummmm yeah....lol

Good luck!

 

Best bet for this data is to pull it from a stock GM calibration for that vehicle. The offset data will be a 3D table by voltage and manifold vacuum. Just use the 0 KPa vacuum data that corresponds to each voltage data point.

Not sure how the short PW compensation data is set up.

RBob.

 

Thanks RBob, I'll look around post what I find.

 

I've been searching for the last few days, and found this post from last year.


Injector Data Sheet: M-9593-AA302, 24 #/hr Bosch 3, 280-155-931

Fuel Pressure: 46 psi

Minimum PW @ 46 psi: 508 usec

Offset Compensation versus Battery Voltage:
6.4 Volts: 2001 usec
8.0 Volts: 1385 usec
9.6 Volts: 1042 usec
11.2 Volts: 819 usec
12.8 Volts: 664 usec
14.4 Volts: 531 usec
15.0 Volts: 491 usec* extrapolate out to higher voltages

Flow rate: 26.1 #/hr

Does the "offset compensation Vs Bat voltage" serve the same function as "Injector pulse width correction Vs Battery voltage"?

 

Yes, they are the same, just different names in the XDF file.

RBob.