I am knew here but I am hoping that you can assist me with a problem that I am having.
The problem is that the truck is limited to @ 50 MPH road speed. It acts like it has a governor. It is not a fuel problem, for sure. And it is not RPM related, since I can downshift and still not change the spot where it cuts out.
Here is what I have; It is a 1996 F 150 5.0 with the 4R70W transmission. The drivetrain has only 16K original miles on it. I transplanted the drivetrain and all of the related parts into a 1963 Unibody pickup. I used all of the wiring, computer, etc. I also have an electronic instrument cluster to match. The only change from original that I had to do was that I wired a VSS into the output shaft of the transmission since I could not use the ABS system.
I sure hope I gave you enough info, as this thing has me pulling my hair out. Everything works great up to 50MPH.

Tim