You probably will want to send your distributor to a shop like Bob Jennings Dyno and have it recurved. The process is not expensive, but it really helps. Blower motors like lots of initial advance[ usually 14 to 16 degrees], fairly quick advance , and only about 36 degrees total, sometimes less depending on how much boost you are running. When a company advertises a certain amount of boost, they are usually expressing wide open throttle and 6000 rpm. Roots type blowers make boost all the time and extra torque all the time. but less at lower rpm, so an engine that would normally have 16 in. of vac at 1500 rpm might show 14 inches.
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