head porting on 2007 apex

[heehaw]

how much HP will i gain in porting my head? and who does the best job ? thanks

 

[yamahas]

Moved to the correct forum, hopefully this will get you some replys.

 

[steiner]

There was a thread about this last month or so about htis.
I think the gain was about 20hp

 

[yamman]

dave at hurricane performance ontario ca. 20 hp.

 

[andrew1984]

what needs to be done to compensate for extra fueling