Intermittent vapor lock problems.
The Oldsmobile Cutlass F-85 was my very first car; oddly enough, I bought it before I even knew how to drive. I bought for $1200 off a guy who worked on the railroad, a real 'cream-puff' (the car, not the guy). As a neophyte I didn't know what the hell I had--the pick-up (acceleration) on this car was impressive, even with the 2-barrel carb (let alone the 4-barrel) --it really threw you back into the seat, and one had to be quite careful on the throttle. The car was fast off the line and the top end was great too--I don't think I ever topped it out, probably 115 mph was the highest I hit, and the car could cruise all day at 85 mph. This light aluminum engine was nicknamed the 'Rocket'--but in this instance the marketing hype matched the reality. I later found out from a southerner that they made these things into stock-cars.
The early sixties in America saw a brief flurry of mid-size cars and the Cutlass F-85 was one of them. Too bad the trend of a powerful, low-slung, and well-handling (by traditional US standards) luxurious mid-size died out--when I was driving the F-85 in the mid 80s, though a quarter century old, it had more punch and equal handling with the 'new generation' Mustangs or Thunderbirds that were coming out.
"Engine and transmission 283 V8 Automatic"
- If that's what that 1961 F-85 had, then someone put a Chevrolet 283 in there.
Ah well, it was a long time ago. it had eight cylinders anyways...