It's a patented idea called ST valves (surface turbulence). For information
look up the metric mechanic.

 

Interesting stuff. I noticed in the little excerpt, it mentions that it benefits both carb and injected motors. I wonder if by injected, they're referring to the older Hillborn style injection, or if they actually mean EFI applications? I was always under the impression that sufficient fuel atomization wasn't a problem with electronic injectors.

 

This one has it done to the face:

http://www.mpgresearch.com/garage.ph...d&image_id=118

Says it's from an '88 Dodge Daytona.

http://www.mpgresearch.com/garage.ph...c737fe1930be05

 

Yes, Scott purchased those from the metric mechanic, I can't remember
if he claimed improvements from the valves. If I remember correctly he
did several modifications at once.

ssheen's Daytona