13 lbs.
After looking at the Pelican catalog, it appears that all normally-aspirated 3.6L between '90-98 can use the same flywheel. Therefore I'd venture to say this flywheel would fit any NA 964 or 993 - but I don't know why the Fidanza catalog (
www.fidanza.com) shows a difference.
According to the Pelican catalog, 964 turbos ('91-94) and 993 turbos ('95-98) use different flywheels. The Fidanza catalog shows this flywheel will also work on a 993 turbo. So it would be safe to say, that for some reason, this flywheel won't work on a 964 turbo.
What is really confusing is that the Fidanza catalog states their 964 flywheel is the same as their 993 RS - but that flywheel is heavier at 14 lbs.