Your right this is the Forced Induction forum

Basiclly with a NA car you get one desprate gasp of air on each intake stroke. In which youve got to suck as much air and fuel as possible.
So you do everything possible from porting to valve angle jobs to get as much fuel and air in.

With a Turbo you have 10 PSI waiting to rush it. The intake valve opens and air is shoved down its throat will a now handle this appraoch.

Sure get a Dremel an match up your intake and exhaust ports. Polish up the exhausts and texture the intakes. But a valve job is a waste of time and money.

 

valve jobs can free up more flow that porting and polishing, and it helps on both NA and FI cars.

5 angle is overkill as the cuts are so small it won't add anything to flow, it will just make the seat smaller and actually hurt long term reliability. 3 angle is key, and done right will provide good sealing, flow, and it'll last.

the port and polish are to be left to a professional, and you won't notice much anyway, if you want more power, get a better cam and a valve job. Life will be good.