I went out to the track today and noticed that my cylinder air mass seemed to be low to me. Whats the cause of this?
I went out to the track today and noticed that my cylinder air mass seemed to be low to me. Whats the cause of this?
Can't help without mod list to know where you may be. Is the car in SD? Is that a wet shot?
Sulski Performance Tuning
2000 WS6 M6 - LS6 (long block, refreshed top end), 10.8:1 CR, 90 mm ported FAST, Exo-Skel, 227/232 cam, QTP HVMC, EWP, GMMG, 9" w/4.11s
2018 Sierra SLT 5.3L A8 - Airaid intake tube, GM Borla catback, L86 Intake/Ported TB
No the car is not running SD, its just a CL MAF tune and the AFR was about 11.5 all the way across the board since im sure you cant see my custom PID's.
It's a stock bottom end 346
233/239 .605/.610 112+2
stock 241 heads
stock ls6 intake
pacesetter longtubes
true duals with moroso spiral flows
slp lid
stock maf
S3 shaner ported and polished TB
150 shot wet kit
There are two things that can throw that off, improper fueling and/or logging a certain PID. I can't remember as I have not had the issue with any of my current configs.
Sulski Performance Tuning
2000 WS6 M6 - LS6 (long block, refreshed top end), 10.8:1 CR, 90 mm ported FAST, Exo-Skel, 227/232 cam, QTP HVMC, EWP, GMMG, 9" w/4.11s
2018 Sierra SLT 5.3L A8 - Airaid intake tube, GM Borla catback, L86 Intake/Ported TB
I really doubt its the fueling considering it was pretty much 11.5 all the way across. What do u mean by logging a certain PID?
are you commanding 11.5?
Sulski Performance Tuning
2000 WS6 M6 - LS6 (long block, refreshed top end), 10.8:1 CR, 90 mm ported FAST, Exo-Skel, 227/232 cam, QTP HVMC, EWP, GMMG, 9" w/4.11s
2018 Sierra SLT 5.3L A8 - Airaid intake tube, GM Borla catback, L86 Intake/Ported TB
I'm commanding 12.8 and it drops to 11.5 on the wet shot.Originally Posted by WS6FirebirdTA00
i'm gonna guess fuel pump is running out of juice, not holding up the pressure it should, injectors pump way less fuel than the IFR table would indicate, and VE goes wild as a result of miscalculation.
It's a racetronix pump and hotwire kit and the pressure idles at about 64 and drops to 57 at WOT.
Have you made any changes to the injector flow rate since you noticed the change.
IFR is stock as well.
does your IFR reflect the fuel pressure drop?
No i haven't even messed with it because i can't log my fuel pressure all i have is a mechanical gauge and its kind of a crap shoot to get it exact.
Does it even matter that my cylinder airmass is low? If not im not even going to worry about it.
yes it matters. airmass gets used to determine other values, notably spark and trans (if auto).
i dont see injectors on your mod list, and you also said you got a stock IFR. are you running this combo on stock injectors?
Yes stock injectors and stock IFR and it is an auto.
Come to think of it, I had my High RPM Disable on my Dynamic airflow tab set to 0 rpms because i was doing some maf tuning on the way to the track. Would this have an effect on it?
no, it just means you're using pure MAF based airmass estimation. if that's off, in addition to your IFR not reflecting reality, get ready for seriously screwy airmass figures.
So u think its low due to my IFR table being off?
i don't think so, i know so
Also, there might be few more reasons, this is however a big contributor, and easily fixable.
how are you doing on pulsewidth at peak tq and hp? your injectors should be out of juice, unless you have a very well designed/efficient setup. wet shot might be only masking that.
Haven't logged pulsewidth but my injector duty cycle was in the 90's on the motor passes. So pretty much i need bigger injectors and rescale my IFR table is what your saying?
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