What exactly is 2-3 flare, and what causes it?

[Jon01]

Trans is starting to act funny in my GN.
Just driving normal, no boost, it'll shift into 3rd oddly sometimes, it starts to shift, then the motor winds up a little, and it drops into gear.
Under boost, it's perfectly fine, shifts quick, not exactly the hardest shift, but I'm only running 13 psi of boost, and a very mild street chip.
Also, twice, I've gotten into it around town, and it's dropped into second, and it's acted like nothing's there, the motor rev's, but car doesn't accelerate.
I know that slippage = dying tranny, but it's only done this twice, and when I accelerate from a stop normally and roll into the throttle while it's in 2nd, it holds just fine, it's only when it's downshifting that it's acted up.
Any ideas?
Jon

 

[Scott231]

A 2-3 upshift flare happens when second gear disengages "long before" third gear engages...relatively speaking of course.

Originally posted by Jon01
Just driving normal, no boost, it'll shift into 3rd oddly sometimes, it starts to shift, then the motor winds up a little, and it drops into gear.
Under boost, it's perfectly fine, shifts quick, not exactly the hardest shift,

Its not because your "under boost", it is because at WOT you have pulled the TV cable tight and raised the line pressure. You should properly adjust the TV cable.

Also, twice, I've gotten into it around town, and it's dropped into second, and it's acted like nothing's there, the motor rev's, but car doesn't accelerate.

That's because there isn't enough line pressure getting to the servo to apply the band quickly enough. Several reasons why this could be happening...talk to a tranny expert.

when I accelerate from a stop normally and roll into the throttle while it's in 2nd, it holds just fine,

That's because you do not need a lot of pressure to make the band apply from a slower acceleration.