I know I read somewhere but can't remember the source that a rope seal, once broken in has less drag than a rubber/viton seal. But that's certainly not the case when the rope is new. I have removed the pistons and rods from old Pontiac engines with rope seals and the crank can be turned easily with 2 fingers. Not scientific, but almost no drag you can feel. As far as the viton seals on serrated crankshafts. I personally don't like Eagle crankshafts so I have never used one in a Pontiac build. There have been many comments on the forum and other sites that some Eagle cranks have very aggressive serrations that could tear the viton seal or leak through the serrations. If you can easily catch a fingernail on the serrations, polishing this area with 280/320/400 cloth would be a minimal treatment IMO. Factory crankshafts I just polish in the normal way with a 400 grit, worn polishing belt and they seem to work just fine with the viton seals.
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