my suggestion is using ur standard 4g91 head then PnP will be better and put ur money on PnP cost.. if u play wif big head like 93 without piston sure not ngam maaa n oso need PnP too for good fuel consumption or torque..
my opinion is you need to find good mechanics for make port and polish cause too many risk if u port not ngam.. polish is not the issue..
my opinion is you need to find good mechanics for make port and polish cause too many risk if u port not ngam.. polish is not the issue..