yes port and polish done correctly will definitely improve performance...
price depending on who is doing it... there is no fixed price for port and polish job...
u can try nastyportflow in usj 1, behind summit.... they have some high precision tools there.... its not like u can try n error when it cmoes to pnp ur car.....
If you in jb can try xh racing,call0197853245.
I did my 6a12 v6 pnp together with 3angle and skim head at xh racing ,jb.price affordable.definately increase hp but need to adjust valve timing.
When BMW engineers took a much-needed break from the 128-degree F weather in Death Valley, they were kind enough to unlatch the hatch of the new X6 for KPG's spies to...
when you install a VTA External wastegate, do you experience boost creeps ??? as in boost increases as the revs go higher...
Do u need a boost controller to eliminate this...