Most any production head from an OEM is going to flow less on the exhaust as compared to the intake. Most cam grinders make a few cams that feature a dual pattern (more lift and duration on the exhaust lobe) to help equalize flow. You can do much the same thing with a higher ratio rocker on the exhaust. Just be careful to watch for coil bind, retainer to guide clearance, rocker to stud clearance and valve to piston clearance when doing this.

Is it worth the money involved? I doubt it. A cam change would probably be more cost efficient.