just did a 2000 b16a2 swap with rebuilt head, ferrea valves, blox stage2 cams, for a friend this is in a 97 ek. i searched but couldnt find an answer for my specific issue. car sounds great during break in for the cams. now when he goes to drive and hammer down like normal when the car should be hitting vtec there is a weird noise and its like the car wants to bogg down..... when the car is sitting still not moving in nuetral it revs fine like it has vtec. i dont know if its a electrical issue or oil issue so im hoping someone will have some input on what he hell is wrong here.

thanks

 

If you lowered your VTEC cossover with out having a computer with remapped fuel programs its gonna bog down.

 

makes alot of sense. so vtec isnt connected to FM? that doesnt make alot of sense. you would think that the fuel and valve control would be linked so that as one changes, so does the other.

 

does putting in cams mess with the vtec crossover?

 

the engine's vtec worked great before the motor was removed due to a popped valve then thats when we swapped it back into the ek with the cams and head work. little more info about what all we did

 

no it doesnt change the crossover, but it does change where the crossover SHOULD be. so when you change anything about the flow characteristics of the engine, you need to adjust the vtec point.

 

id definitely say with the head work and cams, VTEC is hitting too early. the engine isnt capable of flowing that much air at that RPM, so it boggs down. thats my guess. i would definitely suggest playing with the vtec, preferably on a dyno and getting it to the right point.

 

also, these cars have MAP sensors, which is a speed/density system. it GUESSES on the airflow. i takes the TPS reading, MAP reading, and outside air pressure reading and it uses that stuff to guess the airflow. what this means is that if you increase the ammount of air you engine flows but keep the stock programming, the MAP, BARO, and TPS readings can all be the same(and therefore doesnt add anymore fuel than normal) but the engine is flowing more air and needs more fuel.