I was looking at putting a 4.6 DOHC motor in my foxbody coupe until I saw the weight if its true. I know they are more costly to build but, I thought it would be cool. Scroll down and look at the weight of these engines. It states that a 32v 4.6 weighs more then a 5.0.
http://www.strokerengine.com/EngineWeights.html
http://www.strokerengine.com/EngineWeights.html