GSC +0.003" Exhaust Valve Guide Toyota/BMW B58/S58 GSC3131.003-1
Oversized Exhaust Valve Guide for B58 & S58 Engines
The GSC Power-Division +0.003" Exhaust Valve Guide is engineered for Toyota B58B30 and BMW S58 engines requiring additional clearance in custom-machined or high-mileage cylinder heads. Designed with a 6mm valve stem fitment and integrated stopper protrusion, this guide ensures secure seating and helps prevent valve guide drop during high-RPM operation.
Fitment and Compatibility
Sold individually. A complete head requires 12 guides. Standard and +0.001" oversized options are also available to match your builds tolerance needs. Compatible with OEM hat-style valve stem seals or metal clad seals when using alternate spring seat setups.
Key Features
- +0.003" oversized fit for custom-machined heads
- Stopper design for quick install and anti-drop protection
- Seal flexibility with OEM or metal clad options
Specifications
| Stem Diameter | Total Length | Outer Diameter | Stopper Protrusion |
|---|---|---|---|
| 6mm | 43mm / 1.693" | 10.03mm / 0.3948" | 16.5mm / 0.650" |
Fitment:
- 2016–2023 BMW M240i / M340i / M440i 3.0L Turbo Inline-6 (B58B30)
- 2020–2025 BMW M3 / M4 / X3M / X4M 3.0L Twin Turbo Inline-6 (S58)
- 2021–2025 Toyota GR Supra 3.0L Turbo Inline-6 (B58B30)
CA Residents: WARNING: Cancer and Reproductive Harm www.P65Warnings.ca.gov
