Originally Posted by My68Vette
No changes were ever made from when the Trans was recieved new from TCI.. They dont say what type of kit is in it, they only say that it has crisper shifts.. It does not have a full manual shift kit it in because it stil shifts when in drive.. Is something like this adjustable in the vacuum module? The vacuum is hooked up and working because with out it, it wont shift.
Almost all aftermarket modulators are adjustable by reaching down into the hose nipple with a small flat blade screwdriver, in your case turning it counter clockwise to "soften" it, 1/2 turn at a time. Can't go too far though, only maybe 3 full turns out. This will also lower the shift points a lttle too, though. Have you worked on the carb and the distributor advance curve to try to get a stable 950-1050 rpm idle speed?? This is where most of the problem probably is.