| MATERIAL AND LOCATION | COBALT ALLOY SEAT FACE |
| STEEL, FED STD 66, AISI/SAE 3140 STEM |
| STEEL, FED STD 66, SAE EV4 HEAD |
| METALLIC HARDNESS RATING AND LOCATION | 40.0 ROCKWELL C MINIMUM STEM |
| 45.0 ROCKWELL C MAXIMUM STEM |
| 41.0 ROCKWELL C MINIMUM TIP |
| HEAD STYLE | FLAT |
| HEAD HEIGHT | 0.1094 INCHES NOMINAL |
| OUTSIDE DIAMETER | 0.8070 INCHES MINIMUM AND |
| 0.8170 INCHES MAXIMUM |
| NECK RADIUS | 0.2500 INCHES NOMINAL |
| SEAT ANGLE IN DEG | 45.0 |
| STEM STYLE | DRILLED |
| HOLE DIAMETER | 0.0940 INCHES MINIMUM AND |
| 0.0980 INCHES MAXIMUM |
| CHAMFER LENGTH | 0.0312 INCHES NOMINAL |
| STEM LENGTH | 3.8750 INCHES NOMINAL |
| STEM DIAMETER | 0.2460 INCHES MINIMUM AND |
| 0.2465 INCHES MAXIMUM |
| DISTANCE FROM HOLE CENTER TO STEM END | 0.1875 INCHES NOMINAL |
| CHAMFER ANGLE IN DEG | 45.0 |
| CARBON RELIEF GROOVE | NOT INCLUDED |
| FSC APPLICATION DATA | GASOLINE ENGINE |