well they would have a code number on it, like p72 or something liek that, im not really sure on alot of the heads, i normally use the non-vtec versions bc of the power and torque number i get out of them, i use mid flow to make power rather than high lift, when u got mid flow u it responds more, so its more on focus to the mid range a lil more than the high end
torque accelerates u, horse power is a math problem, and it only supply mph
and rule of thumb, horse power dpnt get u down the track quicker