Heads?

[Tycar]

I appear to be leaking oil through my head gasket so i'm setting up to replace it soon. Thinking about taking all the time to undo the head has me wondering:
A) is there anything performance-wise that i could do to the head while its off?
B) is there anything i could install or do to the intake manifold while it's off or the throttle body while i'm at it?
C) is there any other engine that i could do a head swap with? a friend of mine is doing a vtech head swap on his civic and it seems so easy to get so much more power, especially when i need to take the head off as it is... any other engines i could do a head swap with when i have a 99 sentra gxe with a GA16DE?

[slideways...]

1)3 angle valve cut, JWT camshafts(i think they have GA16 cams...), find someplace with dual valve springs, titanium retainers, and after that you can flash your ecu to raise the redline a little

2)if you trust yourself you can hand-port and polish the runners on the manifold and the ports in the head, or take them to a machine shop and have it done.

3)most nissan heads are very similar in flow characteristics, and they dont have cheap vtec heads. im not sure if a sr16ve head would work or not, but it is very expensive and requires LOTS of modifications, especially electrical. that is even if it works in the first place

[Tycar]

1) what is the three angle valve cut?
2) How exactly do you port and polish and what would you be porting and polishing? any links to pics?

[mmcleo11]

1) Port & polishing is best left to the professionals. It involves taking metal out of your cylinder head ports to smooth out the flow of air(basically, giving a knife edge) Taking too much out of one cylinder and you have a fucked cylinder head.
2) 3 angle valve job, involves optimising the air flow characteristics of the engine thru the valves, promoting swirling of the gas mixture.
3) SR16VE head swap is a no go(SR motors are alloy block with different bore and cylinder spacing) but fit a thin metal head gasket and bump up your compression ratio for some more power.