Join Date: Jan 2005
Location: New York, NY
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737NG/MAX and A320 are not materially different in terms of cruise speed. Obviously, lots of factors besides capability of the aircraft go into actual cruise speed in service.
757/767 slightly faster, and 777/787 are faster still. Comparing inflight time on same sector between A32X/737 and 777/787 would show that the WB is generally faster.