It was the Buick 215 cu in engine. The Rover engine had cast steel (?) cylinder liners which cured a lot of the cooling/piston problems. The last one I had was still going strong at 160,000 miles when the body let it down.
In an era of fiddly British engines with CB points, valve adjusments etc, the Rover V8 with it's electronic ignition and hydraulic lifters was a maintenance free wonder. Shame about the fuel consumption though!