The guy I bought it from in Iowa got it from the original owner in Texas that built the engine. So, the guy I got it from didn't have all the info. I asked him what the compression ratio was when I bought it, and he wasn't sure, but thought 10:1. So that lines up with a stock 69. I should have said I wasn't sure and have not confirmed the compression ratio. The engine came to me with Bosch wr8dc+ plugs, I replaced with RN9YC and no change in problem. I changed to the RN12YC along with timing change and its better but still some rough. It's in the lower rpm range, 1600-1800. The plug wires are orange Mopar electronic suppression G.X. 1-00 AATH. You can see them in this picture.
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