That makes sense. The bottom of the ports are just out of line with a straight path for the airflow. The ports could have been made higher, much higher, but no intake was really much taller than the first single planes made for it. I have a NOS Torker in the box, planned to put on a 400 before strokers existed.
The exhaust ports were what needed the most help, again way too low, bottom of ports wasted volume. It's like the designed the heads to go into a car that was 18" shorter and narrower than the big cars they actually put them into. The 69 Mustang had plenty of space to use an intake 6+ inches taller, and headers that'd come straight out for 2-3" at least. Maybe the same engineers that built the Explorer exhaust manifolds, did the Cleveland heads. They certainly were not car guys.
91 Mark VII LSC SE - soon OBDII and 4R70, GTC kit and 347, custom paint.
1998 Mountaineer, 98 Explorer Limited to soon add 4WD, XP8 parts, KB blower, paint, 332.
99 Limited mail vehicle, SOHC 4WD. 72 Ranchero 351 project