ws6rufus

iTrader: (6)

I finally maxxed out my stock screened MAF at the track last night. Im Lucky I didnt blow the motor up because in 4th gear I went from a 10.6AFR@5400rpm where the MAF maxxed out, to 14.7AFR@6200rpm at the end of the 1/4 mile. I did a search but didnt find any definative info.

Im almost positive Im going to go with a stand alone system next year but how can I band-aid this until then? I have LS1 edit and already extended the MAF to the max of 511.99Gm/sec@11750HZ.

Thanks

MECHAM

iTrader: (4)

add more fuel in the power enrichment

GMC SKI

You have to add Fuel based on the when the maff hits it's limit
At what rpm .Then you need to manually add fuel in the PEvsRPM table
Try adding 3%fuel when the A/f Starts to climb

MIGHTYMOUSE

iTrader: (59)

congrats.. you using the original maf? what year car? 99+ i take it..

send me your file or i can send you my old one

ws6rufus

iTrader: (6)

I tried adding more using the PE table @5600rpm and 6000rpm and the AFR went really rich after 5600rpm in 1st-3rd where the MAFS is'nt maxxed out. And it really didnt seem to help in 4th gear. How do you prevent adding too much fuel @ a given rpm in lower gears where the MAFS isnt maxxed out.

At the same time the MAF maxxed out in 4th gear(5400rpm) my injector duty cycle started falling linearly with the rise in AFR from 74% to a low of 53% @ 6200 rpm. Is this just a symptom the MAFS maxxing out? My fuel pressure held steady @ 74 psi(14lbs of boost)(base pressure of 60 psi). I also got a steady rise in Knock retard from 0@5400rpm to a high of 9@6200 but that was obviously a consequence of the AFR going lean.

MIGHTYMOUSE

iTrader: (59)

found this, basicallly how my pe table used to look. when i maxed the maf at 3600rpm

you have to tune for the worst case scenario, you are right you will be richer in the lower gears.. stock maf

it will look more exponential if you are able to hold boost, when i was running that tune i was not holding boost so i wasnt adding as much fuel.

GMC SKI

do you have an EFI log for it can't understand why your injectors duty cycle would be going lower

ws6rufus

iTrader: (6)

Heres a copy of my EFI log

GMC SKI

Wow that's Quite a bit of timing your running with your setup
What do you have done turbo ?
I would first Say go with less timing on that thing
I'm at 18 degrees of timing at wot that should get rid of some of that KR your seeing
add some Fuel In the PE table and try it again

ws6rufus

iTrader: (6)

Ive got a T76 QMP kit. Timing has not been a problem. I have alcohol injection along with the intercooler that came with the kit.

SILVER BULLET

iTrader: (1)

My Granatelli MAF is maxed out so tomorrow I am installing a custom calibrated Pro-M ford MAF. It is designed to support 850 hp. I should have some new numbers in a week or two after relieving the bottle neck

BigPlanTransAm

maybe add another alcohol injector and set it to come on at like 5200rpm in 4th gear?

GMC SKI

which Alky Kit are you running you might be out of flow
The alchol explains all the timing you are running
Is the system still working ? You maybe out of flow in the upper ranges
maybe not enough flow for the amount of power Like Bigplan suggested