Anybody every play with or run a 576 head

Below .250 lift, flow is mostly reliant on the curtain area and valve job.
It seems like there would have to be something out of “ordinary” for a 1.60 valve to be flowing more than a 1.88 valve in those lower lifts.

Something along the lines of the intake valve being lowered in the chamber to help facilitate a valve to piston clearance issue........ which would def kill off some low lift flow.

I don’t know how much better a 576 ex port is than a 308 head, but I prepped some 308’s for a NHRA stocker, and on those the ex port was never better than the intakes.
At .100 lift they were basically even when a back cut was added to both valves.
With the back cut on the intake valve only ....... the ex flowed less at all lifts.

Intake flow over exhaust flow with back cut on intake valve only:
.100 - 10
.150 - 13
.200 - 19
.250 - 30
.300 - 40