The catch can keeps the oil vapor from the pvc out of the throttle body/plenum, keeping the inside clean and not carboned up. A strut tower brace ties the shock towers together, helping stiffen up the front end for better handling/cornering.
Welcome! I live just across the river from you on the Illinois side and am on my 3d Challenger - love them! If you have any questions or need help with anything, private message or e-mail me! [email protected]
Welcome! Green with Envy is one of my favorite Impact colors.
bad8nti summarized both mods well. If you will never tune your GwE, and don't care about performance and think a car is just a commodity to get from point A to B, then you don't really need a catch can....
...but then, why would a GwE Challenger catch your eye?
I can honestly say I was surprised at how much a difference the front strut bar made to the ride. Definitely worth doing. It has been documented however that unless you're doing road courses or autocross, there is little performance difference between the many brands of strut braces; aesthetics and price are the only real variables.
Catch can will prevent oil from going back into your engine from the PCV system and help reduce knock. Not necessary for normal driving, but for high performance use it is helpful.
Front strut bar will improve cornering and stability to a degree. I had one installed in my old 2010 R/T and noticed a definite improvement in cornering. It seemed to handle bumps better as well, seemed to tighten things up a bit.