Supertech black nitride intake and exhaust valves for 4G63 Evo, DSM and GVR4. These valves are available in various sizes to match your head diameter. Intake and exhaust valves are sold separately or as a set of 8. For a full replacement you’ll need 8 intake and 8 exhaust valves. Please do all your research and consult your engine builder if necessary!
Black nitride valves are made from one piece forged stainless steel then go through a special hardening process to lessen the friction between the valve and guide.
Vehicle Fitment:
1992-2006 Evolution I-IX
1990-1999 Eclipse GST/GSX
1990-1998 Talon TSi
1990-1994 Laser RS
1991-1992 Galant VR-4
| Fitment: | Size: | Includes: | Part Number: |
| Exhaust | Standard 30.5mm • Stem Diameter 6.54mm • Length 109.6mm |
8 Valves | MEVN-1007-8 |
| 1 Valve | MEVN-1007-1 | ||
| Exhaust | +.5mm Oversize 31.0mm • Stem Diameter 6.54mm • Length 109.6mm |
8 Valves | MEVN-1008-8 |
| 1 Valve | MEVN-1008-1 | ||
| Exhaust | +1mm Oversize 31.5mm • Stem Diameter 6.54mm • Length 109.6mm |
8 Valves | MEVN-1009-8 |
| 1 Valve | MEVN-1009-1 | ||
| Intake | Standard 34.0mm • Stem Diameter 6.57mm • Length 109.6mm |
8 Valves | MIVN-1007-8 |
| 1 Valve | MIVN-1007-1 | ||
| Intake | +.5mm Oversize 34.5mm • Stem Diameter 6.57mm • Length 109.6mm |
8 Valves | MIVN-1008-8 |
| 1 Valve | MIVN-1008-1 | ||
| Intake | +1mm Oversize 35.0mm • Stem Diameter 6.57mm • Length 109.6mm |
8 Valves | MIVN-1009-8 |
| 1 Valve | MIVN-1009-1 | ||
| Intake | +2mm Oversize 36mm • Stem Diameter 6.57mm • Length 109.6mm |
8 Valves | MIVN-1010-8 |
| 1 Valve | MIVN-1010-1 |
The “Black Nitride” is a hardening treatment that is applied to the whole valve whereas the chrome coating is only applied to the stem. The microhardness is higher than the stainless steel base material, keeping good ductility beneath the hard nitrided layer. Microhardness is 800HV minimum.
The Black Nitride surface finish is smoother than with chromed stems, having less friction between stem and guide. The higher the engine speed the bigger the power loss due to internal engine friction! The Black Nitride reduces this power loss due to less valve-guide friction.
The MEVN-1007 exhaust and MIVN-1008 intake are pictured.
