this is at 10psi on my FD. 2nd, 3rd, and 4th gear.

mods are:
haltech e8
intake/downpipe/midpipe (stock catback)
full non-sequential
stock injectors, stock fuel pump, stock IC

AFR's in the low 11's, high 10's.
advance is ~16*, split is ~12*


question 1. how the hell could i be hitting 98% duty? my fuel pressure is not dropping off
question 2. whats up with the RPM spike halfway through 4th gear?




here's the datalog file http://www.streetelite.net/pics/Cart...r_disaster.csv

 

Your PRI and secondairy duty cycles will be different keep that in mind, log them sepratly.

If your hitting 90% I would guess its on your primaries just before staging.

 

Looked at the datalog, log secondairies and report back, what you can do to fix this is reduce the staged disenrichment, what I would do is reduce it by about 1 MS (AKA 1000 YS) and add about 5% to the map after the staging bar and then continue tuning

 

i didnt see an option to log them seperately. i thought they all logged as one...

 

its in there sepratley, you'l see it. They can't be logged as one input as they DC will be different figures with the staged dis staging mode.

this staging mode is an order of magnitude better than common mode

 

thanks for the info, colin. this new software is so fancy!!! secondaries are hitting ~75% duty

here is a new datalog:

http://www.streetelite.net/pics/Cart..._disaster2.csv

 

.

 

Pretty much what I said before, increase the staged dis enrichment by 1MS slightly increase the fuel after the staging bar and continue tuning

tune to between 12-11.5 to 1 at 10 psi, on stock turbo's.

Running into the 10's your will be dumping greatly excessive amounts of fuel into the engine for stock twins at that boost level.

You might well run out of injectors before you hit the limit of that 2 bar map sensor.

 

here's my last one.

i increased the staged disenrichment by 1ms and had to richen up the secondaries a bit. got the AFR's into the low-mid 11's. now the primary injector duty is about 85% by redline.

 

You could continue to increase the staged dis-enrichment until the injectors have about the same duty cycle at peak power (they would still be different everywhere up until that time) and then you would truly be at max safe power at 85% DC, maybe around 11PSI.

Personally, I would get bigger injectors.

Perhaps just an extra set of 850's. primaries would get up up to 13PSI, at which point you would be needing a new map sensor.