Ok didn't understand a word but you think it won't work ?
The problem is that I used to have a ping of 40-50 and a download rate of 7-8 mbps and now it is down to 80-100 ping and 2-4 mbps. Is swapping my cellular antenna could be helpul ? I also have to replace my home button so I was wondering if I could change anything in there to improve the performance while I'm at it ?
Form factor aren't the same means that the size and shape are different between the 4 and the 4S's antennae. You really won't get much better performance altogether unless you replace the antenna and upgrade both the processor and the RAM, which isn't possible. Meaning you'll need a new phone if you want increased performance
The antenna band (the iPhone's frame) from a 4S will not work w/ iPhone 4 internals. All the mounting points are different... and it just simply won't work. The iPhone 4 processor, logic board and peripherals are designed to work w/ the iP4 antenna... not the 4S antenna.