I have two cars with Pontiac 400's. They both have 62's which are the same as 16's execpt they have more bolt holes for air conditioning components. My 69 is stock and the 79 has pistons to lower the compression. I'll post a link to the exact pistons at the end. Both need some octane boost over the 93. I read that you had 16's but I didn't know which pistons you have.
