14b, 510's, s-afc, and maf-t = overrun

[suprdave09]

18lbs on a 14b, with a maf-t blowthrough setup all zeroed in with tuning from my s-afc. Base fuel pressure set at 38 with aeromotive FPR. I have 3" exhaust, ported turbo, manifold and o2 housing. 2 1/2" upper intercooler piping. Question is i keep overrunning the maf with this setup. I dont understand why....i had no knock 18-20' timing through all rpm's. Pulls from 2nd-4th. Then about 3 hours later after letting car cool down. I ran into the overun. I leaned out 4,000 rpm's to 7,000 to try and decrease hz and bam 12 counts of knock and still overunning maf. I am at like 96 % injector duty. I am -24% high throttle on the safc. Is there somethin im am missing, do i not have enough fuel.....or just too much boost. I can run 16l lbs no problem. Please help and thanks.

 

[steve]

How do you know your overrunning the MAF?

Steve

 

[suprdave09]

well then i am getting fuel cut, which to my knowledge is overunning the maf. Any help would be appreciated.

 

[steve]

Two different things.

If your getting fuel cut, where the ECU turns off the fuel and you slam into the windshield then first check for boost leaks. Anything leaking out will raise the metered airflow leading to you hitting fuel cut earlier. If your intake holds your max boost pressure without adding air then you'll have to get an EPROM ECU or larger injectors.

Overrun is when the MAF starts dropping counts and becomes erratic in measuring airflow.

Steve