08 E38 LS7 Injector Flow base

[Age08]

Is there a custom OS that allows larger flow rates for 08 E38?
Currently in process of installing a blower on LS7 and it came with 80lb@ Bar3 injectors,(plans to run E85 in future).
I see the tune max out at 7.99 grams/sec for injector flow base and a 09 ZR1 tune is good for 15.99 grams/sec.

[joecar]

If the 16 g/s OS is not compatible with your ECM, then you have to scale...

( you can scale IFR/STOICH_AFR to avoid having to shift-down many tables )

[Age08]

I just read about doing it that way, I was gonna try just with IAT multipler, have you tried this way before?

[Age08]

does anyone have a stock tune for 2011 Z06 LS7?

[joecar]

You could also use the IAT multipler to scale.

[Age08]

Joe,
what tables do you mean B4001 & B3671?
I have tried the IAT multiply to scale but it doesn't seem to work very if at all, If I understand correctly that IAT multiplier would do this B4001 * B1213 = a number that is greater then 7.99? so the pcm would reduce injector pulse to produce correct rate.

[joecar]

Yes.

Please post your tune file (if you can), I want to look at the injector tables.

[Age08]

attached is modified IAT modifier as well as the injector flow correction from the injectors.
21677
I just tried adjusting the stoich_afr my the % difference in IFR and the car idles not bad. The question I have isn't changing that gonna screw up the closed loop afr?

[joecar]

...
I just tried adjusting the stoich_afr my the % difference in IFR and the car idles not bad. The question I have isn't changing that gonna screw up the closed loop afr?
No it will not mess up closed loop... LTFT/STFT detemine closed loop, and you will see SAE.LAMBDA be hovering right on 1.00 in CL (even tho the commanded AFR shows 29.36).

( remember: the ECM uses EQR and/or Lambda for fueling, AFR is for your viewing purposes, not for running/tuning )

[joecar]

Joe,
what tables do you mean B4001 & B3671?

Yes, those two tables... they scale inversely wrt each other (for example: B4001 * 0.75, B3671 / 0.75)


I have tried the IAT multiply to scale but it doesn't seem to work very if at all, If I understand correctly that IAT multiplier would do this B4001 * B1213 = a number that is greater then 7.99? so the pcm would reduce injector pulse to produce correct rate.You would go B4001 * X and B1213 / X where X is your scale factor (e.g. 0.75 in the example above)...

i.e. so now B4001 is below its 8 g/s or 16 g/s limit, but B1213 corrects it to produce the actual flowrate.

[Age08]

Scaling the IAT Multiplier doesn't seem to work for injector this size.
The only way that works for me was scaling both the IFR @ 54% and making up the rest with the Stoich,
I guess the hard limit for injector size must take into account the IAT Multiplier that's all I can think of why its not working.

[Tre-Cool]

i've found the iat modifier works invertly.

if you want to pull fuel out you go above 1, not below.

[Age08]

That's what I did but it didn't work,
I was using 1.84 as per the difference calculated from the g/s rate used in the FPR to the actual rate.

[The Alchemist]

so If I'm running 60lb/hr injectors in my 2007 Holden ( IFR maxs at 7.9999g/s ) then I could halve the IFR table provided by the manufacturer and enter it in B4001 thus keeping it under the 7.999 maximum then change the B1213 values to "0.5" to double the fuel volume thus giving me the correct fuel pulse overall.?? And everything else stays the same like fuel pulse adder, flow correction etc etc

[Highlander]

The IAT multiplier won't work for going over the 8g/s limit. Might as well just flash (or maybe pcm swap) a newer 2011 up cal. But you would have to find your clutch pedal type parameters to make it work....

[JCA]

hi guys, im trying to scale injectors on a later os everything is fine when up to temp short trims withing 5%, but from start up till 40-50 degrees engine temp afrs are dirty rich in the mid 10 afrs, ive got normal values in the open loop tables etc, which I could fudge but im thinking its not idea vehicle is on pump fuel with 750cc injectors