Are you sure the rockers are adjusted correctly? That will make it feel like there is no power if they are too tight, I ended up 1/4 turn on my rockers to get them set right. Are you sure it was at TDC when you installed the distributor, it could be a tooth off.
Make sure you have the right firing order, I know that is something simple bu that will do it, and bump your fuel up to 38psi it slounds like the popping is a lean pop coming out the MAS.
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