7/16-20 is the thread size used on SBC crank snout. BBC is 1/2-20. You'll need threads if you plan to draw the new damper on with an installation tool or alloy all-thread. Otherwise gentle heat then drive on with a big dead blow hammer. I've read stories about aftermarket dampers having undersize bores. It wouldn't hurt to measure your new one and compare to your crank snout. I'm guessing 0.0005-0.001 diametral interference would be appropriate. Anyone know a spec for this interference fit better than my guess?
