Where did Honda get the extra 40 HP from.

[NvrDne00]

Does anyone know what the difference is in the 98-02 and the 03 and on engines? I guess my question really is where do they get the other 40HP? Its the same 3L VTEC right? So is it cam, piston, type of induction, Vtec tuning, or something else? I heard from an source that I am not sure is reliable that its all in the intake or induction. If this is true does anyone know where I can get the parts necessary to make the upgrade and gain the 40HP? Also, any suggestions on brand/type of intake/exhaust. Any help is highly appreciated.

Sean

[stab]

They increased the HP by doing valve work and increased exhaust flow. Is what I read at Honda site anyway.