A 1965 Pontiac Grand Prix found it's way home with my son last week. He has ambition but lacks experience so what better way to correct that, jump in. His find included a 1963 383 motor and we need to mate these two together. I have messed with my share of Fords Chevy's and most recently my 50 Mercury, I know nothing about the old Pontiac. In this call for help I am trying to pin down what motor mounts and frame mounts we need to round up. I have included a picture of the motor mount that came on the engine but for the life of me I do not seem to understand what frame mount needs to be used. I imagine that I have only half of the mount and that it is the wrong style for this swap, my best guess. Pictures suppliers and any suggestions are very welcome.
Would be a 389. Not sure, but don't know if the '63 motor will hook to the '65 trans. There was a change in that stuff around those years.
'65 was the change year, '63 is going to be tough to adapt plus you are going backwards. Anything from '65 up will bolt in without much fuss. Dad put a 455 in his '65 with no problems, used the same T400 transmission it came with. The '63s had a crap transmissions and you need an adapter to fit anything better in it's place. It will better to keep hunting for a newer motor. Firebird headers for the big car chassis, and most blocks up through 1973 are drilled for the correct motor mounts. The later blocks also fit with a little swapping of mounts and brackets.
IIRC that the 63 starter bolts to the trans, and the 65 starter bolts to the block. If this is true, using the 63 motor with the 65 trans you cannot mount the starter without drilling the 63 block.
The '63 engine might be more of a pain in the ass than it is worth only because of the starter and transmission compatibility issues, although the engines themselves are great. The good news is any garden variety V-8 Pontiac from '65 on up will fit your car and transmission. A 300 dollar Craigslist 400- 2bbl out of a four door wagon looks exactly like a '65 389, just don't tell anybody..... Lots of cool speed parts for Ponchos too. Good luck, -Abone. PS. There are a few good Pontiac engine threads floating around here if you hit the search button.
The motor mounts bolt right onto those tabs sticking out from the crossmember FWIW. Unless it's a stick and you have the right 63 bell, what everyone said above, not worth the effort.