Here’s an example of a reworked SSR vs one where the entire bowl was generously enlarged, including the SSR side of the bowl, but the form over the SSR was not addressed.
2 different 906 heads with 2.08” valves
Quite a bit more bowl work on the one without the SSR done, along with it having a valve job done where the seating angle(45) extends out past the edge of the valve, and has a quite narrow area of contact with the valve itself.
The one with the SSR rework has a std 3 angle seat.
The below .300 lift flow for the big bowl head was surprisingly good, but the lack of SSR rework came into play from .300 and up.
A- big bowl
B- reworked SSR
Flow at 28”
Lift—— A/B
.100—74/65
.200–153/137
.300–204/202
.400–237/251
.450–239/256
.500–240/258
.550–237/262
.600–232/258