i have a couple of questions... first i have an 84 mustang gt... engine started smokin so i replaced with another. thing is i bout it off a guy for 300 hundred but he just told me he got it off a mustang but didnt tell me the year... well i know there is a roller motor and a non roller i need help figuring out the difference to find out if its a roller or not... ive dropped the engine in.. it turns on but too much fuel is droppin in the engine that it bogs out. i placed the four barrel carb off the 84 gt on it and i am figuring that to b the problem but i would like to b for sure.. also do 84 mustnags have a fuel pump inside the gas tank? i know the block i took out had a fuel pump up front that connected to the timing chain cover... which i put on the motor i dropped into the car.... need advice thanks