Is that a TF twisted wedge head? Is so, do that thing was horrible. It took a bunch of work just to get it decent.
The first set I did was right after I got my flow bench. I fixed them and all the rail birds were sure I butchered them.
Couldn’t get him to go to the dyno by he picked up 3 tenths.
IIRC that was the head was had an 18 degree angle on the intake valve and 23 on the exhaust.
They didn’t do well because they just weren’t that good.