It's because the Ford (and Chevy) 427 engines were essentially the pinnacle of high performance in the 60's. The stuff dreams and memories were made of.
Pinnacle: The highest level or degree attainable; the highest stage of development.
IMHO there is really one "pinnacle of high performance in the 60's", that would be the 427 SOHC. The leaky FE just doesn't measure up to the SOHC
