Tall is for the injector..smart or that would eat up advertised flow I'd think.
Wouldnt you say a 360 int port is tall by most standards.
Afaik..The LS head typically does 220s-240's stock. A mildly worked x head or j will do that. An ootb sm head is about as good, under peak is 10cfm behind ..but peaks as good or better.
At this point its get a master for a 300 cfm speed disassturds and copy that with a head that's already tube'd pinch and head bolt right out of the gate .but with a better chamber.
Or be odd just for us oddball stocker head guys..do some aluminum stocker X/J heads that are master cnc to 290cfm ootb with a slightly larger magnum style exh port and ootb at 185cc w/slots not holes..for the push rods...cast in the entire roof about .080 taller on the outside for raising...pedestal rocker if you must but consider bosses for stand mounting/shaft type... and toss a heart-shaped chamber in there for the hell of it and an open option or the meat to make it so kind of like Edelbrock does if the heads actually sells