nothing i have really noticed. my mileage has stayed right around 37mpg. i have talked with other tuners about the l15a head and no one is porting it cause that just weakens it because honda has the wall thicknesses really thin already. i might later on clean up the combustion chamber and do some valve work too.

 

What about polishing the ports?? If we can't do the Port job, maybe we just can do the Polish one!!?

Marko!!

 

you can polish it if you want. i have not done any work to the head yet. i have ported and polished the intake manifold aluminum section though. no real gains though. i would try this on a spare motor first if i had one cause its risky business with the thin port walls.