Poly Engine what was good/bad about it and why is the LA better?

All I know is, in the early 70's, stationed at NAS Miramar, and my street driven pretty-much-my-only transporttion 70 440-6RR would run low 13's with 3.54 gear. A guy "I used to know" showed up in a stock class 63? B body with a Poly and big 2bbl and ripped off 13.0's. I don't remember what class they built it for, he claimed "it was right on" the national record, and THIS was the first runs with the car

If you search around the video might still be up.......someone at engine masters built a poly. I think they actually used an LA block?? I've forgotten the particulars

This is not the engine I was thinking of BUT

Daniel Boshears Brings a Poly 318 Stroker to the 2018 Engine Masters Challenge

Another one