Hey all... last summer I swapped out a 2.6L engine for another one and since then I cant put my finger on some of the stuff thats going on with the engine. First off its not my DD so I dont drive it all that much and very rarely on the main road. it usually is only driven on the farm. it starts up nicely everytime and idles right in between 800-1000. problem is when Im actually driving the car. when I hit the gas to the floor when Im pulling up a hill it seems like the engine is having to catch up to itself. it starts out really slow and then builds up and finally gets the RPM's up where it should be. I have replaced the fuel filter and air filter checked all the vacuum lines, I dont know what to do next? could it be out of time? thanks

Chris