Tranny questions?

[gtxdude]

Rebuilt 904 last year, put about 4600 miles on car this summer. My question is, using a cable kickdown set-up that is adjusted correctly. The car shifts fine when in drive, shift points are where they should be, BUT. When I shift manually which I do a lot because I like to bring the rpm up before shifting. When I bring rpm up from 1st to 2nd (around 4 to 4500rpm) when I shift to second it tends to shift slowly, I would like to have the firm shift. When I shift from 1st to 2nd at lower rpm it seems to shift right away. From 2nd to 3rd seems fine, shifts right away. Would that be a valve body issue or torque converter issue? Over all the car runs fine. I'm just trying to tweek a few things on it over this winter. thanks

 

[AJ/FormS]

Things I would try, in order of easiest to hardest;
Maybe tighten up the band some.
A little more line pressure might do it.
And a stiffer spring in the accumulator.
One of the higher ratio apply arms could help.Anything over 4.0 really. The higher the better, but anything in the 4s is easier to find.

I drill and tap for a small plug, to be installed right where the line-pressure adjuster is. That way I only take the pan off once, and can mess with the pressure all I want to. Make adjustments in small increments. No more than 1/2 turn initially, 'til you see how your tranny responds.

 

[gtxdude]

Thanks