My truck has a 305 the motor it self runs fine... it just doesn't have take off power. You push on the gas and it just bogs fir a couple of seconds and then takes off... I have replaced the o2, mapp, pick up coil, plugs, wires, fuel filter, tps, computer, checked the timing, checked the timing chain, "HELP" i don't know what else to do..............

 

try replacing the computer coolant temp sensor,(Not the one for the guage). I had to do that to mine. If that sensor is failing, it will fun fine at idle and at speed, but can cause the fuel mixture to be too rich at certain rpms. that could cause bogging. The part was about 15 bucks at the dealership. I have been told that the ones that you can buy at autoparts stores fail very quickly FYI. The ACDelco one is worth the money. Hope this helps