I have a 2006 Chrysler 300C 5.7lL V8 hemi AWD. Has 286,000 mi. On it.

About a week ago I got engine knock coming home from work. I love this car and want it to be stronger and faster. would it be better to swap the engine or have it rebuilt, or would it be better to just buy a knew car? considering I'm driving my dad's to get from point A to point B.

 

Only you know what to really do. Salvage Yard engines, of unknown miles and quality, $2000-$3000. That still needs to be installed, by you or other$
Rebuilding todays engines with very close tolerances and having circulated metal probably not a plan. Jaspar or other Reman engines likely $3500-$5000 with a warranty.
Evaluate the entire vehicle. Tires, Brakes, Trans, Suspension, Body condition and potential rust, interior, seating, etc including the cloudy headlights.

Don't get me wrong, I am emotionally attached to my 2002 300M with 230,000 miles on it, but is it practical????

 

Ditto

 

As of right now everything else on the car except maybe the transmission (still great but might need an upgrade) is great and looks practically new. The only rust I have is up on the hood and fenders and only from rock chips so very small. I want this to be a performance vehicle and would rather spend on a new engine for a car I've already put money into than sell it and start over... But if it makes more sense to start over than I'll eventually be able to let go.