As far as I know, the V8 is lighter, but yes, the V6 is built further in towards the windshield than the V8 was.
The majority of articles seem to state the opposite: either stating the ‘V6 is slightly lighter’, or in some cases “crucially it's far smaller and lighter than the V8” (
source of quote)
As Porsche were involved with the engineering development of the V6 and it is a more modern engine, I would be surprised if it was heavier than then Rover V8. I’ve had the
pleasure of helping to pull one of those out of a vehicle and it certainly hadn’t been on a January diet
