Just got myself an Shark Racing 4-2-1 header and MBRP 2.25" exhaust w/ high flow cat. I got them used so I’ll be cleaning them up, wrapping the header, and installing them with my new Elantra intake cam 
. $250 for the exhaust components, and about $200 for the cam with new gaskets. Should be good for at least 10whp combined.
(pictures borrowed from their respected owners)