I read somewhere that the Ford V6 is even slightly heavier than the Rover V8. The difference is that the V6 is placed more towards the center of the vehicle.
As for the torque, even though I found the S1 to be the much sportier and for me the preferable engine for the sum of its characteristics, at least subjectively in comparison the S2 was equipped with a bit more torque from lower revs. And the sound from the S2 was rather silkier and pleasantly fuller in the cabin, while the sound from the S1 was a bit more throaty and metallic. But these are 15 year old memories.
