Any exhaust leaks, pre turbo?
Does the wastegate rod have tension on it when installed? Meaning, do you pull the rod with some force over to attach it to the swing valve? Or is it adjusted out enough to crack open the swing valve when installed?
Could you have blown a turbo hose off?
Are all the turbo hose clamps tight?
All vacuum lines installed?
Did you go from a stock turbo/stock torque converter combo, to just bolting on a TE-44?
If so, you would definitely see some turbo lag.
We need more info and we're all here to help.
Patrick