3.1 swap to to 3.4,one artical on swap said use 3.1 balancer.that was ked85.The other said to use the 3.4 balancer.why ? I have them both but want to use the best one.also ked85 said use the 3.4 exsaust manifolds,where the other one said to use the old ones.which one do I use?The oil pan was also different in there write ups.the EGR off the 3.4 wouldn't be the same as the 3.1 would it?

 

Balancer doesn't matter which you use, I would just use the one on it, unless the other has less miles/wear on it, manifolds I'm not quite sure on as I have headers so used neither manifold set, I've heard the oil pan is hit and miss, but I had no problem using my 3.4's oil pan fortunately(mine had some rust and a dent or two and was non painted, 3.4 pan looked practically new and was painted)
EGR might be the same but I am unsure, I know the 2.8 EGR is definitely different, not to mention vacuum instead of electronic.
But these are all things that will answer themselves when you get the engines side by side and look at them.

 

ok,thanks for the input.