Looking for suggestions and experience With upgraded the sedan

2010 models

How much can you afford to spend?

Is it Normally Aspirated or supercharged?

The supercharged engines have more upgrade options.

OP's thread title says NA.

Really not much you can do with the N/A unless you want to spend huge amounts of cash & then you're better off buying the S/C model. All been asked before.

Maybe put XFR brakes on as some have done. A search will turn up a few threads that should answer any questions.

I just want to the know the process if it’s possible and what all I can even do to upgraded if I was not to supercharge it

Remove engine and all modules. Fit new engine with appropriate modules.

If you don't have a budget how do you know when to stop spending money and buy a different car?
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One of the vendors here told me the 4.2 NA could gain maybe 25 HP with a performance tune. Not much in the way of additional equipment or HP gains to be had for this engine.

The supercharged engines have many more options to gain HP.