Nope, any engine from any manufacturer, but must be the same year or newer and retain the original emissions equipment. Now, we did a 5.2 Magnum swap into an '84 Ramcharger, but it would have been no different to do a 5.9 or even a 5.7, 6.1, LS1, etc. A swap like that must go to a referee who does not determine if the car is clean, but that it has all the correct equipment. They make a new sticker for the vehicle. In our case the Ramcharger would forever be smogged as a '96 Dakota. Then a smog station determines if all is working.