[Limitless_BRZ]

Originally Posted by BRZoomTX

My own personal opinion about Delicious aside, the current tune is not dialed in well as already mentioned. Adding a 3" turbo-back wont fix the issue you're having here. Your 2.5" will easily flow enough air for your current boost level.

Before your pull your LTFT is near 20% indicating idle and cruise MAF scaling is not dialed in well. During the pull, you start rich then lean out on the top end, it swings from ~4% too rich to ~5% lean; nearly a 10% variation in fueling during your pull. Your MAF g/s curve is also bumpy, especially on the top end, and contributes to why your fueling is off.

Your tuner [Delicious] should have you do much more low end MAF scaling before having you do these pulls. The car does not look ready to be driven hard yet. Just my $0.02.

Your current MAF scaling will be causing more of an effect on your drivability than your 2.5" overpipe. You can run a stock catback on a turbo and not suffer from such issues. You won't make the best power but you shouldn't feel anything along the level of thinking the car is pulling timing.

Regarding timing, you are actually running a couple degrees more on the top end than the low end, so over time it is adding timing, not taking it out. You did have knock event early in the pull but IAM remained 1. Delicious will want to look at that area but please have them address your MAF scaling first.

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