904 shift problem

Yes the throttle pressure linkage is what everybody calls the kickdown linkage. You back it off by shortening the linkage at the carb. That normally makes them go into gear quicker but since you now mentioned that it don't kick down like it should it sounds like it may not be adjusted tight enough and if you back it off any more that problem will get worse. Another possibility comes to mind and that is an adjustment that is easy to do but would require dropping the pan to get at. On the drivers side of the valve body where the throttle valve (kickdown valve) goes in there is a stop that sets the idle (best term I can think to call it) If it is set too far in it will basically give the same effect as holding your trans in passing gear which will cause the harsh part throttle shift and delayed shift. Overlap is when a trans is shifting and is still in the first gear momentarily and goes into the next gear. Many shifts kit uses a restrictor to slow the engagement of 3rd gear so 2nd has time to drop completely out before 3rd comes in so overlap don't happen. I had one case that had overlap from 1st to 2nd so severe that when the wheels were jacked up and it shifted from 1st to 2nd the wheels nearly stopped then took off again.
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