Warning: this message contains my opinion. No facts were hurt in the creation of this opinion.
A 930 is a 930 due to turbo lag, burst of energy. Somewhat scary reputation. And will climb in value, because Porsche fans will pay big money for its performance, flaws, and character.
A LS conversion will likely be awesome. Exorcize all the flaws. And be "better".
However, IMHO you have removed the character. And resale will be to a much smaller crowd. And they want you to take the $$ hit. Speculative Porsche buyers will ignore it.
Just my thoughts on retained value.
My guess is a LS conversion would be a blast to drive, sound like a rumbling monster v8 and be pretty cheap to maintain. A cool concept.
I saw a 944 with a 2010 camaro engine. Wicked fast. Wouldn't mind that at all. Within character. Already a smooth water cooled engine, just better.
A 930 with a LS? No.
A twin turbo conversion with a big wing covering a too large inter cooler and shorty pipes blowing flames on trailing throttle. That'd be on the list.
