My original mags coming with the engine got close to 500 hrs on it, time for 500 hour inspection. The mags were running fine. Left mag was 4373 (impulse coupler with 25 deg lag), right mag was 4370. However, I got a SUPER good deal on a pair mags, 4370 and 4372, with less than 100 hours from a friend. The 4372 mag has a lag angle of 15 deg. My engine is IO-360-M1B with timing on the data plate as 25 BTDC. If I time the mag to 20 BTDC (I know I will sacrifice a little power by doing so), can I use 4372 mag with 15deg lag? Has anyone done this? I am concerned about kick back.
I am also thinking about swapping the impulse coupler between 4373 and 4372 (after inspecting the coupler), which is less preferred at the moment. Is the coupler (or impulse coupler shell which determines the lag angle) the only difference between 4373 and 4372 mag?
I am also thinking about swapping the impulse coupler between 4373 and 4372 (after inspecting the coupler), which is less preferred at the moment. Is the coupler (or impulse coupler shell which determines the lag angle) the only difference between 4373 and 4372 mag?
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