After an engine swap from y7 to y7 (blew the old one), my speedometer has acted very funny. When idle and in park, it stays at 5 mph and while driving, it's always 10 mph faster than what I'm really going.

Notes:

1. No check engine light.
2. 3-pin connector that goes to the VSS got lightly damaged and 1 of the wires doesn't 'clip' into the connector and it had came out a few times but I have since shoved it in pretty hard and it stayed.
3. VSS is known good.

Any ideas on why the incorrect readings? It's never done this before!

 

I would get that VSA connector figured out, especially if right after it happened you had speedo issues. That wire falling out may be causing a weird connectivity issue making the speedo head act funny.
These civics are notorious for speedo heads to go out in the cluster. So that issue is lurking as well.

 

Sounds like the speedometer is toast.