727 shifting late

Postby EV26pack » 30 Jun 2005 23:31

Still going through my new car!
Most of you now this car as Jack's JS23V0B.
Anyway The car shifts great in all gears under
light to moderate acceleration. But under heavy
throttle it is fine between 1st and 2nd but really
is late from 2nd to 3rd. Even shifting manually
it really hesitates to go to third. Any ideas?
I took it to a guy who is highly recommended
and he wanted to know what kit was put in it.
He also showed me how to adjust the throttle linkage to change the
overall timing of the shifts.
Any info would be greatly appreciated!
Thanks!! :s004:
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Postby dave-r » 01 Jul 2005 7:42

You want it to shift late for performance. Unless the rpm it shifts at is really very very high.

Shift kits normally increase the shift rpm.

What do you call late anyway? What rpm is it shifting up at? Bear in mind that the stock tach often reads too high.
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Postby EV26pack » 01 Jul 2005 15:48

Hi Dave-
Late feels like 6000 or higher. (Only 2nd to 3rd)
But what bothers me is the shift is not deliberate
and when manually shifting it should go to third when I shift
not hesitate 3 to 5 seconds later. I have adjusted the throttle linkage for earlier shifts, but it has no effect under full throttle use.
Jack says there is no kit in it, but I don't know how a 727 could shift that hard without some modification.
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Postby dave-r » 01 Jul 2005 20:59

I can't think of anything that would only make 2-3 late.

If it only happens with the throttle down quite far or hard to the floor then it has to be something to do with the kickdown linkage or the kickdown valve.

But if the valve was stuck or the linkage set up wrong them it would make the 1-2 shift late too I would have thought?
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Postby Follicly Challenged » 05 Jul 2005 14:38

Does it tend seem to be "hanging up" between 2-3 before the actual shift ? or is the actual shift just really late, but crisp, when occuring ?

If the latter, you may want to turn down the regulator pressure on the side of the valve body to compensate. Requires pulling the pan, turn the screw in to lower as the screw is engaged to a cage that applies spring pressure.
Just a thought, as many older shift kits used to require drilling of the orifices from the pump to the valve body to increase flow and in effect retard the governor pressure buildup to cause the upshift. Backing off the throttle pressure side by lowering the regulated pressure might allow earlier governor pressure to overcome sooner. Easy to try by pulling the pan.

If the former, and seems to "hang-up" between the 2-3, just loosen the 2nd gear band a quarter turn at a time until happy. Doubt it's the band adjustment though, you're trans guy woulda caught that.
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