If you can post the part numbers stamped on the breaker plates of both distributors, I can probably find information on the centrifugal advance specifications. There's also a possibility of a mismatch between the distributor gear material and the camshaft, so it might be a good idea to swap gears before using the 216 distributor. The shaft diameters are the same, IMHO, so a swap shouldn't be a problem.
Jerry

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