2-3 shift issue?

1983 c6 in my f100.. 504cid 463hp, 580 ft,tq.
I reset the band, I put a green stripe modulator in it. changed the fluid , installed a deep pan and put a factory small block high stall torque converter in it. and I still have a issue with the 2-3 shift feeling like it goes into an imaginary gear for a second before going into third.

It sounds and feels like it leaves second gear... then does this weird thing... maybe slips... for like a second.. then engages into third and drives fine.

Any idea's

What servo/lever combo are you using? Any valve body mods?

Yes exactly, What is done to the valvebody?
What is the history of the trans ?
What is done to the trans? As in clutch count in top gear ?
What did you set the band at?

If you want to think of it like this , The band releases faster than top gear applies. The flare you fell is the trans momentarily in 1st gear

Was the flare there before you did that work on it?

its a used reman trans. with a stock valve body. tightened up band all the way and backed off 1-1/2 turn

A stock trans , and trying to put power through it ? Not surprised

well its doing it at moderate driving... where there isn't much power going threw it. Its slipping for sure between 2-3 and it takes a full second between getting from 2 to 3

It's not a slip as such , it's more poor shift timing .  You could try screwing the modulator in, some cases it MIGHT tidy up the shift a little . If it is stock it's not going to last . Next step would be get the valvebody out and some mods to help it survive . The stock 3 top gear clutches will struggle.
I never use a stock valvebody even on mild or stock setups  , they just shift way too soft and slow

do you think a shift kit would do it? as far as just upgrading the valve body. I'm going to get red alto clutches & band with kolene steels and freshen it up ... any suggestions for the servo?

A shift kit may help. I often use the Transgo 67-2 . It increases the 2-3 feeds . and may help

Truth be known a stock valvebody just won't cut it

The red clutches are good . You really need to add clutches to the high clutch if it only has 3

As for servo , depends what you have now , and what lever . Some of the factory ones will get you by ok .

The usual upgrade is R servo and E lever

if i shift it manually it works fine... any thoughts on that. I just tried this last night

You likely find shifting manually you are accelerating. The vacuum is lower under load so the pressure that bit higher for the shift. At part throttle there'd be vacuum so lower line pressure.

Have you tried screwing in the modulator or a longer pin? . Might bump line pressure just enough. I have seen that work before .

I've put a 100 miles on with no issue other than my 2-3 ... if i shift manually its fine....
I put a new modulator in and adjusted it twice. 2 turns in right away and then 2 more later .... I'm going to try a different modulator and see what happenes ... this issue started after i change it

A couple things to check. Not all new modulators are good.  Some are shipped with weak springs and will cause early shifts and a 2-3 flair.  To check, pull the modulator out and check the tension on a small scale. Insert the modulator pin ( unless you are missing the pin and there's your problem ) push down on the modulator against the scale and note the "weight" at the moment the pin starts to go up into the modulator. I don't like to see less than 10 1/2 lbs tension.  The stock pin length is 1.700" . If yours is less it can shift early/soft. Also, never connect modulator line to anything but manifold vacuum, and never to a line leading to a vacuum reservoir. HTH

Tonight, i turned the modulator out 4 turns. 2-3 shift delay is 50% less.... so it shifts much faster and the 1-2 shift is firmer.... the rod is in the trans.
this is a greens stripe i got from the local parts store. thinking about trying to defect this one out.

a little bit of history. the transmission used to shift way fast and just dump into gear, that y i changed the modulator. and it was bad. fluid was going past it into the vacuum line.

Adjusted the shit out of modulator.... no help..
If i shift manually it shifts perfect