There's only so much of an injection window up top there. Fueling from the pumps isn't an issue as rail pressure is good. It's quite a stout tune. E85 on an IS38 is hard to nail down without MPI. It's always right on the edge of what the DI injectors can handle. Some cars can get away with it, mainly because their pumps are probably not 84% E. OR they run a bit less boost. Try and cut in some pump gas and see if that alleviates it. Heck, you'll get a bit better mileage, lol.
Do like a 10/2 split on an empty tank.
Reopening an old thread for discussion as I've been fighting a high rpm misfire for almost a year now. Finally got Simos Tool's to do some logging.
misfire starting at 5800~ rpm. Engine compression tested 150-155psi across all cylinders, no odd sounds from the engine. less than 40,000 miles on the car. No fault codes except random misfire or if it shuts down a cylinder (EPC) it will throw a code for misfire on that specific cylinder. Misfire count in the log is low for some reason even though it's breaking up super bad and will throw an EPC light if I stayed in it.
Log:
https://datazap.me/u/tehfalcon/misfire-near-limiter
APR DTR6054 Turbo
APR DTR6054 ECU Tune 91 Oct
APR DTR6054 DSG Tune
ARM Catted Downpipe
APR Coil Packs (tried OEM ones as well, same result)
Brisk ER10S Spark Plugs with 0.024” Gap
ECS Intercooler
ECS Intake Duct
RAMAir Intake
Mishimoto Radiator
Fluidampr Crank Pulley
CTS Catch Can System
CTS Throttle Pipe
Any thoughts? I'm leaning toward it being a fueling issue now