What would changing my ecu do?

I have a 1997 honda civic dx coupe automatic. I have a stock ecu in it. I also have a p2p ecu and a p28 ecu. What would happen of i were to swap them out. Would i have increase power. Or what would happen. And do i need anything speacial to swap?

The Ecu has to be matched to the engine. If you change something about the engine (cam profile / compression / turbo etc) then you need to change or modify the ecu to match.

So changing the ecu on a stock motor doesn't achieve much, and may even make it perform worse if things are mismatched. Just "swapping" your ecu isn't going to do anything. You need to know what you're swapping it for. Go through with the manufacturer. The car wioll not run well if at all. You have to match the engine

Just "swapping" your ecu isn't going to do anything. You need to know what you're swapping it for.

Go through with the manufacturer.

The car wioll not run well if at all.

You have to match the engine