vtec kicks in beautiful on my b16 but it bogs before it kicks in what should i do ive replaced the wires plugs and distributer cap and the rotor that i can get is circular does it matterif mine is differently shaped

 

You have to modify your cap to mount correctly... Also, check out your fuel filter... Mine was on the car since new and at 195k with a B16 it wasn't putting out any pressure. Swapped in a new one (Buy one for the car, not the engine) and it had not a hint of hesitation at high RPMs.

 

o2 sensor can cause this also. do u have a stock ecu?? two o2 sensors ?