Shift points are controlled by the tension on the bowden cable. If it's adjusted too tight, your shifts will be late and can be excessively harsh.

Vacuum at idle on the vacuum amplifier setup is usually somewhere around 12-15" of vacuum. Higher isn't necessarily bad at idle. You should see the vacuum rapidly drop to zero on the line to the transmission modulator when the accelerator is actuated. By 1/4 throttle or so, you should have no vacuum at the modulator if everything is adjusted properly.

It's important to know what the vacuum levels are at the VCV line on the blue UFO to properly diagnose its operation. You haven't given us that info yet. Without boost, the blue UFO output to the transmission modulator should largely correspond to the vacuum level at the VCV line. The blue UFO is there to refine the shifting based on engine load (boost pressure) rather than solely from throttle position like the earlier cars.

Don't adjust the blue UFO. They can wear out internally. If you always have full vacuum going to the transmission modulator regardless of what the throttle position is and the vacuum level from the VCV line is, you could have a failed blue UFO. Rule out all other possibilities first.

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