i have a friend that has a 93 eg with a b16a, it has several mods and it has the cx wiring,it has an upgraded p28 i dont know what program,any way when my friend uses a stock ecu the vtec studerers when the throtle is partial(not when is all the way to the floor)he got the car as is and he doesnt know if it has engine work.

would it be because it has high comp. pistons and the air/fuel ratio of a stock ecu is not enough????