Recent content by passerby

Try this article as a basic primer. http://grapeaperacing.com/GrapeApeRacing/tech/intakehelmholtz.htm

Automotive companies do not lap valves they use precision machined valves and seats. Sometimes they use a slightly shallower valve angle 44 1/2 against a 45 degree seat which assures a line contact and tight seal. A engine operating temperaures this will pound in until the seats are parallel at...