Oversize U20 Stainless Steel alloy Race Quality valve set. Our valves are not regular commercial, two piece design, which can fail at the head OUR valves were specifically designed by Manley Performance Products for us with Mark Degroff's recommendations who is a expert in engine rebuilding for 45 years
Not made from blanks or from another motor or made in Argentina out of 214 stainless.
Intake on the left and Exhaust on the right. Swirl polished intake and exhaust valves, hard chrome stem through and through, NOT flash chrome. High flow head seat design, weight saving dished face, 50RC keeper groove & tip. Will not mushroom.
Intake diameter 1.845 - Original Nissan 1.815
Exhaust diameter 1.460 - Original Nissan 1.420
NOTE: No new seats need to be installed with these valves. It may be a good idea to install new seats for the intake if they are brass or if the seats are worn. Hardened seat part numbers are: 1494 & 1820.
Mark Degroff's Cylinder Head Service approved the drawings with a top valve manufacturer during the design process. Mark has been custom designing valves and has experience working with cylinder heads for 45 years when most of us were in elementary school.
Criteria for GUIDE clearances: INTAKE .0015 to .002 / EXHAUST .0025 TO .003
Be sure to check all clearances
Our valves are notRepurposed valves like smaller vendors that work out of their home garage.