there both 4 bolt motors.... i know complete history of the 83 motor the onley thing i know about the 78 is that it has a cam and that its so tired lets just say that i ran it at the local 1/8 drag strip lancaster ny and it took me 13.872's to get down the 1/8 mile
....talked to my machine shop a few weeks ago before i bought the newer motor he said with the componets i wanted to use i would be making around 550 FT lbs and arond 500 horse not to bad for a n/a motor haha .... with that i think im goin to blow up my tiny 10 bolt that has a 100,000 miles on it lol but dont have the money to get a 12 bolt anywho ill take pics of the vally on the 83 tomarrow dont realy want to take the 78 apart its my onley vehical for the next week to i get the bonnivile done for my mom then ill get my car back thanks alot for everyones help!!!!