GSC Standard Intake or Exhaust Valve Guide Set for Porsche 996/997 GT3 Cup – GSC3997-12
The GSC3997-12 Valve Guide Set includes 12 standard-sized guides designed for Porsche 996 and 997 GT3 Cup engines. Suitable for either intake or exhaust use, these guides are precision-machined by GSC Power Division to fit 6mm valve stems and deliver consistent performance in high-output builds.
Fitment and Quantity Notes
- Standard size – sold individually or in sets of 12
- Oversized options – available individually in +0.001" and +0.003" sizes
- Full engine build – requires two sets (24 guides total)
Technical Specifications – GSC3997
| Specification | Inches | Millimeters |
|---|---|---|
| Total Length | 1.673" | 42.49mm |
| Outer Diameter | 0.4160" | 10.57mm |
| Valve Stem Diameter | — | 6mm |
Engineered for Porsche GT3 Cup applications, this standard valve guide set ensures reliable fitment and long-term durability for intake or exhaust use.
Fitment:
- 2000-2005 Porsche 996 GT3 Cup (Intake & Exhaust)
- 2006-2012 Porsche 997 GT3 Cup (Intake & Exhaust)
Note: These guides are compatible with both intake and exhaust positions. A full engine rebuild typically requires 24 guides total (12 intake + 12 exhaust), so two sets of 12 are recommended.
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