Costs and effects of these mods for the SOHC motor?

[Afboy143]

70mm TB/75mm MAF,
24lb injectors,
extrude honed and ported heads

I saw these mods on a sig of someone's and they claimed to have a 4.6L explorer. My question is, how much would each of the above mods cost and what would the gains be? What did this guy do to make his explorer 4.6L over stock 4.0?

 

[explorer99xlt]

if i remember correctly and i am sure someone will correct me if i am wrong but i believe that its the v8 size

 

[pfeffer1728]

the newer explorers have a 4.6 v8...older ones have 5.0 i believe. i dont know what years exactly

 

[Green98XLT]

4.0 is the V6
4.6 is the SOHC Mod V8 used in 2002 and up Ex's
the 5.0 was in the 95- 2001's I believe.

Either way those mods would be pretty effective although I would imagine the porting and polishing of the heads if done correctly would be very time consuming and costly.