So did the car with the blown engine actually run (except for the engine being blown)? If it ran, and all you've done is replace the engine, there obviously shouldn't be much wrong except for a minor oversight during the engine install or something like that. If whoever you bought the car from was messing with it after the engine blew, you will have to make absolutely sure that you know the condition of everything in that car or else you have no idea what you're actually dealing with.