Hi all,
I installed AMS900x kit with AMS 3,5 intake and tried to scale MAF/injectors w/ID1000cc. But faced with huge problem to find out correct multiply data for MAF scaling. With 1,39-1,41 multiply it doesn't work corect (AFR is too poor ~18-19). As I have a new turbo and completely different intake I decided to return stock injectors in order to find correct MAF scaling data at first and only then try to scale ID1000 injectors.
I was little bit surprised when I've got MAF multiply around 3,8 (LTFT close to zero, STFT runs around -/+2, AFR 14,0-15,5). I thought it should be closer to 1,39-1,41 but not 4
Have you ever met such multiply MAF scaling? Am I doing something wrong?

 

To me it sounds right. I tried a long time ago to use the 1.4 and the car was way too lean. But I agree best to tune it with stock injectors and then install the ID1000's.

Sounds like you are on the right track.

~Kris

 

That seems very big!!

does anyone with the AMS 3.5 intake have rough scaling they could post up?
I recently had a play with one and it really was all over the place.
I started at 1.4 and it was way too small for idle and cruise. I ended up just incrementing up in ECUFlash but I'm sure i didn't go much past 1.7 or so. I'll have to check.

When i worked out the area Vs stock it was pretty much double.
would it then make sense to need 2x MAF scaling?

 

When I calculated area difference it shows 1,96 multiply but even with it AFR is very bad and xx jumps crazy. I started to increase multiply as LTFT and STFT was 12,5+ and after few hours I've got the 3,8 as the best throght LTFT/AFR point of view. But this is twice more than theory. That's confuse me.

 

yes ... nearly 2x is what i found for the area.

i didn't have time to scale the MAF thoroughly - but my trims did the same as you, always +12.5 very quickly. it will take hours to get it right.

did you scale the MAF with stock injectors in? you really need to.
I scaled FIC1100s with the stock airbox, trims perfect, then put the 3.5" intake on to scale the MAF seperately.

what MAFvolts are you logging at idle?
I managed to get the idle trims around +5 and cruise trims around -7 (yes, this makes NO sense!)
i ended up with around 1.55 for table 1 , about 1.48 for table 2, and i made 1.45 for table 3 but it doesn't look right on the 50%+ throttle logs - Load is too low.
I just "smoothed" the transitions between the tables. It's very rough, it was just to get the car running!!
I need to start all over again i think. Double check injector scaling with stock airbox, then do the idle/cruise logs with different MAFvolts and scale the intake properly.

 

I should add idle AFRs with FIC1100 very stable - 14.3 - 15
Cruise AFRs also are good.

check your fuel pressure
i see you have the 340L pump - you may have fluctuating fuel pressure?
maybe use stock airbox and stock injectors and check your fuel trims first before trying anything else

 

Yes I did scaling with stock injectors. I can’t place stock MAF so I selected other way. Start to scale MAF with stock injectors (I know stock latency and there is no problem) and only after that try to scale ID1000. I didn’t install ID1000 yet as not 100% sure 3.8 MAF multiply is correct.

1.28-1.36 volts

I have Fuelab pressure kit with gage - and the fuel pressure set at 40Psi

As I mentioned above now it is set to 40Psi. I didn’t find out the stock fuel pressure numbers so I can’t be sure that everything is correct.

No chance to use stock MAF, too big turbo inlet. It seems the way to start scale MAF with stock injectors also correct. I just started from the other end

 

^^ AFAIK stock base pressure is 43psi, stock pressure at idle (vacuum) about 37psi.
please someone correct this if it is wrong!

yes your procedure seems correct

idle volts for me 1.26 - 1.37. mostly 1.30-1.35
cruise volts i can't find many logs but 1.7-2.1volt or so

weird....
you have the same airflow, fuel pressure is ok.
The USA guys will be awake soon maybe they have some good answers for you