Can part throttle shift points be changed with HP Tuners? I have a semi built 4l60/3200stall in my trans am and it's in 3rd gear before 20mph also it's in 4th and the converter locks up while entering a highway and it really lugs the engine unless I almost floor it to downshift. What if anything can I adjust to help/fix this? Thanks in advance.

P.S. I've googled this question and all I can find was WOT shift points