Misfire/ spark blowout driving me crazy

[ayousef]

car is am 08 427 TT C6 Z06 with an HPT 2.5bar SD tune.

the car would only go up to 7.5psi without misfiring, anything above that and it misfires crazy.

The last time it did this I was sure I had (not so good) wires which were a little burnt from the manifold, but this time I have new coils, wires, plugs everything. FYI #7 plugs gapped at 0.30, I dont know if its time to close the gap a little more though.

Still didnt put the car on the dyno to verify, but on the road it seems to misfire at the same boost level, my local dyno tuner ran out of ideas himself and said its not in the tune.

ill post up a log where in every instance above 105Kpa Map I let go only after it mis-fires, just so you know when its misfiring.

Im also thinking MAYBE the pass. side turbo inlet MIGHT be collapsing under boost, but I did not verify that yet.

Can anyone take a look at this log, and see if you can come up with something?

ambient temps were: 35degrees C.

PS. sorry, I hope this doesnt sound weird, but I dont think my tuner would like me to post up "his" tune on public, unless someone can offer direct help, thanks for understanding.

[MNR-0]

The log doesn't really indicate much for me. If it is breaking down, check your boost with an external boost gauge and it wouldn't hurt upgrading the coils

[ayousef]

The log doesn't really indicate much for me. If it is breaking down, check your boost with an external boost gauge and it wouldn't hurt upgrading the coils

Exactly, nothing shows on the log, at least thats what i thought as well, I dont know though how a misfire looks like on the logs.

The coils have been working on vehicles up to 1300HP, so I doubt it has anytihng to do with the coils even as little as 7.5psi of boost.

Im trying to come up with a conclusion whether its a tune/electric related misfire, or perhaps that turbo inlet pipe is really collapsing, but again if I knew I wont be asking, so all options are viable.

any other suggestions/ideas?

[LSX378]

It wont hurt to gap the plugs a little lower like down to 0.025 or 0.020 and see what the result is.

[firefly9r68]

how long have you been under boost? is it a stock ls7? if it is you could have a cracked piston or ring, seen it MANY times. drives find runs fine, but MISFIRES under boost. you need to get a HISTOGRAM to log misfires for each CYL and then that will tell you EXACTLY what CYL is doing it and you can speed up your trouble shooting process that way!

[ayousef]

my car only misfires over 7PSI of boost, and I never heard of cars running fine but not boosting because of broken rings either, can you clarify :S

by a cracked ring are you suggesting a compression leak? if so then its most likely not the issue as I did a few compression tests recently (after the problem)

edit: low-comp forged warhawk LS7x, not a stock motor.

[Street Legal]

my car only misfires over 7PSI of boost, and I never heard of cars running fine but not boosting because of broken rings either, can you clarify :S

by a cracked ring are you suggesting a compression leak? if so then its most likely not the issue as I did a few compression tests recently (after the problem)

edit: low-comp forged warhawk LS7x, not a stock motor.

have you adjusted the spark plugs gap ? down to .030-.028

TT cars dont like more than this Gap.

[ayousef]

bro you probably missed this, but my plug gaps are already 0.30, I dont know if going down a measly 0.02 to 0.28 would change anything >.<

[Street Legal]

bro you probably missed this, but my plug gaps are already 0.30, I dont know if going down a measly 0.02 to 0.28 would change anything >.<

yes it would make a difference,i had a customer's car that did the same thing and was fixed by gapping it down a bit.

[NICKY BOY]

try using this config yet?