First What do our cars weight. Second What is the differance between the 4t65e-HD and 4t80e. I was thinking it was wierd that a Bonnie GXP with a lower output Northstart motor has a seemingly better trans. Being as GM's trans power handling rating goes up withthe number u know 4L60-4L65-4L80. And what would it take to use one in a GXP. Other than the starter issues.

 

Look at your door for what the car weighs ?

4t65eHD and 4t80's are completly different, they just don't fit. It's much cheaper to put some goodies in your 4t65eHD.

There's a reason that GM uses the 4t65's in their FWD drag cars.

More than a few 4t65's take 500whp daily. You might want to go on Club GP for advise on that.