S4 trans to s5 trans
 

Really need to know which one is better. I really think they are the same. To some people I heard that the s4 is stronger but the s5 is lighter. Help me out I would of searched it but my search isn't really working that well or my computer is slow and i dont think my computer is slow.

Uhh really i need to know.

I'm assuming you mean N/A compared to a turbo transmission? The turbo tranny, for sure. If you're talking about Turbo/Turbo between S4/S5, I can't imagine anything being different except for the chassis and bellhousing of the tranny. NA/NA should be same. I don't know of one being stronger than the other, but more than likely I don't know what I'm talking about. :)

I swapped out an S4 to an S5 on an N/A before so the least I can tell you is that they'll fit harness and all. I'd assume the S5 is stronger as it's newer and has to handle those extra rev's and hp the S5 motor puts out, but I could be wrong.