Speedmaster Small block porting tips and results Part 1
“Serdi” is a brand name of engine rebuilding equipment.
They make a variety of stuff, but their name is usually associated with guide and seat machines, which can be used to machine valve seats.
I don’t have a Serdi brand, but I use another brand of machine for that job that’s also popular in the performance industry....... a Sunnen VGS-20.