the biggest part to doin that is that you have to changer the wiring harness also
well the biggest problem your going to run into is that the 2.4 in the gt has direct ignition eg the coil pack and coil pack housing with the two two you will have to get spark plugs wires and probably a distributor cap rotor button and find a place to mount the so in essence ya there is going to be some mods needed
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