[n2oiroc]

my car is fine in 2nd gear, but 3rd gear on up it falls flat on its face above 6,500 rpm or so. i logged it and didnt see anything except a little timing (-2.8*) being pulled right before it happens. no misfire being picked up either. it didnt do it on the dyno either. the only thing that was changed since the dyno runs was the plug gap, i closed it up from .030 to .026 because the tuner logged a slight misfire at 7,300 rpm. it almost feels like its running out of fuel or hitting the rev limiter, but it shouldnt be.

so far i checked the crank sensor gap and its tight. idc's are in the upper 70% range. i added a 12gauge ground from the block to the battery and unless im imagining things, it seems a little better. any ideas?

07 sti
new 9.5:1 built block
T3/T04S u.r. turbo kit (65 lb/hr compressor .82 a/r turbine)
stock heads and cams
12mm jdm oil pump shimmed .040"
one step colder ngk iridium ix plugs gapped to .026"
tgv deletes
deatschwerks 1,150cc injectors
walbro 255
perrin fmic
blow thru maf
tial 44 ewg
tial bov

[reid-o]

Try and post your MAF readings. I've never run blow through on Subarus, but I did on DSMs. At high loads (I ran a Red), the airflow gets really really choppy and the sensor just doesn't like being under pressure. What's worse is that problem or issue is intermittent.
When you look at blow through logs, you really have to give it up to the tuner if the car runs smoothely. All you usually see are erratic numbers past a certain boost level and rpm.

Also post your fuel curve.

[reid-o]

Also, tuning in 1st and 2nd is usually pointless because the engine goes through cells so quickly there are hardly ever issues.
Misfires are usually at high loads when the engine is forced to pass SLOWLY through the rev range, like 3rd, 4th and 5th.

[n2oiroc]

Originally Posted by reid-o

Try and post your MAF readings. I've never run blow through on Subarus, but I did on DSMs. At high loads (I ran a Red), the airflow gets really really choppy and the sensor just doesn't like being under pressure. What's worse is that problem or issue is intermittent.
When you look at blow through logs, you really have to give it up to the tuner if the car runs smoothely. All you usually see are erratic numbers past a certain boost level and rpm.

Also post your fuel curve.

the maf was at 4.3 v right around when it happened, and smooth until then. i cant figure out how to post the logs, but i can email them. the issue seemed to only pop up after i regapped the plugs, but i havent logged and misfires. also he ran it in 6th on the dyno to try and get it to spool faster, no issues then.

[n2oiroc]

alright, on wastegate spring pressure its fine, revs cleanly up to 7,500 rpm. i guess ill ask my tuner whats next. it looks like the plugs cant keep it lit, but i dont know why it wouldnt show up as a misfire. i guess its time for a tighter gap, different plugs, etc.?

[n2oiroc]

update: tried different plug gaps and it doesnt change anything. race gas didnt change it either! now im running 20 psi and less total timing. its better but still there. here are 2 vids if it helps!

YouTube - sti sputtering #1

YouTube - sti sputtering #2