Sold a motor to a fellow two weeks ago, I thought it was a 401. Turns out it was a 364. It came out of a '61 LeSabre with a rear sump pan. He wanted to put it in his '63 Riv, and I knew enough about the Riv to be able to tell him that the Riv would need a mid-sump oil pan, so I gave him a mid-sump pan to go with the motor. What I forgot was that he would also need a mid-sump pick up, at least until he called and said that the mid-sump pan wouldn't go over the rear-sump pump and pick up. No problem, I thought. I told him I'd bring over a mid-sump pump and pick up. He had the motor upside-down on an engine stand, so when I got there, he dropped the pump in, set the pan on, and everything looked good to go. Later that evening he calls and says neither of the bolt holes line up, so he can't use that pump. The pump I took him was out of a Riviera 401, so I'm guessing he needs a mid-sump pump from a 364. Would that be right, or are there other options? Which Buicks had a mid-sump 364? Thanks in advance.
All 364s were rear sump. He will need to have a mid sump pick up adapted to the 364 pump. Carmen or one of the other Nailhead providers may already have something available (sticky thread near the top of forum).
It should be pretty strait forward once you solve for the pan and oil pick-up issue. The 364 has the right bell housing and crank flange to fit the Dynaflow in a 63 Riv.