89' 2.9 v6 with no power!

[Amiddleton]

Hello all,
I recently put a 2.9 V6 into my bronco ii, from a wrecked one. It has been progressivly losing power to the point that it will barely do 60mph, and the tranny jumps all over the place? Could I have hooked up something wrong? I have replaced the fuel pump and ingnition system... please help.. thanks

 

[RonD]

Dirty fuel line filter will slow you down.

Compression getting low will also, either from rings or valves although these are not usually abrupt power losses, also timing chain skipping a tooth or two would cause a lack of power in a hurry.