POP!
 

During a rolling acceleration from 2.5k rpm through a right corner turn in AT Sport 2nd gear lost power then coming in line there was a resonating "pop" and the power was restored.

My guess is that the fuel mixture became over dense (rich) and burn was incomplete, but exhaust gas contained enough fuel to ignite in the cat.

Anyone else noticed this?

Anyone else have another guess what happened?

I hate to say it, but my car does this too. Every once in a while while its may be 2 min of run time from a cold start, i get a pop like an intake back fire. Today I drove our FR-S and actually notice its just slightly happening too. Very strange. I hope to capture this once we can start tuning these cars.

Definitely had this happen once or twice in the first 1800 miles, but not more than that.

Haven't heard this yet, but hopefully it gets taken care of - even if its not a common occurrence it is an occurrence. :(

A pop in exhaust is "afterfire". A "backfire" is in the intake path and is disastrous. I wouldn't worry about any pops in the exhaust.