Where can I find more info on the valve body mod for a 4th gen auto or a shift kit for the same?

My 1-2 shift is pretty harsh but everything is smooth afterwards. The problem I have is if I am in third and mash the pedal, it takes a loooong time to upshift and then my tach redlines (like there is slippage in the tranny). Aside from this, the car drives great and downshifts fine, its just the upshifts that are not correct and the harsh 1-2 shift that occurs as well.

I can't really floor it to pass a semi or anything because it will just wait wait wait wait, then BOOM, upshift and redline the car....

I've tried varying degrees of giving it gas to make it upshift but it wont do it unless I give it a lot of pedal. Coming to a stop, the vehicle seems to hold 3rd and second a bit longer than normal before it upshifts into 1st.

My Max has over 200k on it, but the fluid looks good and the engine runs great.

 

i just did my valve body with 130k miles on it.....1-2 will be very harsh for you. I have stage 2 and at times depending on how much throttle it is harsh. Downshifts are definately faster and you will still have that lag when coming to a stop although its not as bad. Only problem I seem to be having is a sometimes hard shift to OD which I think might just be the tranny going. Im not sure since i had the soleniods replaced when the vb was done and it didnt do it before. Either way i love the way it shifts compared to stock and you learn how to gas the 1-2 to ease it. How does your OD shift? The vb was only supposed to change the 1-2 and 2-3.