Speedmaster intake porting. Hopefully I can make something out of this

Decades back, I was running a Torker on my 440. I'd spin it to 6600RPM every weekend at the track.

I kept reading magazines that without exception extolled the virtues of the dual plane intake. Only an idiot would run anything else. So, I ordered a new Edelbrock Performer and swapped it out. The next day, I drove it to the track and that was one of the few days I left early....the engine would get to about 5000RPM then nose dive. Kinda like what it feels like when you run on down a concrete sidewalk then transition to sand. The Torker went back on, and 6600RPM came back.