Hello from Australia! I have an engine with an MSD crank trigger and 7AL-3.
If I set the trigger up to align with a magnet on #1 TDC at 29° advance, it fires at 10° advance. I've indexed the trigger wheel to make it fire at 29°. However, I'm concerned there is interference or something which could cause it to advance up during a race and blow holes in pistons. Distributor phased correctly. Photo attached showing when the plug fires compared to wheel position. Can anyone explain why there could be such a lag in the trigger wheel to plug fire? Thanks and all the best to the USA folks in this COVID time. Jason
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