Cometic Nissan RB20/RB25 .030 inch MLS Exhaust Manifold Gasket, 1.575 in x 1.340 in Port, C4177-030

Fits Nissan RB20 and RB25 engines.

The Cometic C4177-030 MLS (Multi-Layer Steel) Exhaust Manifold Gasket is engineered to handle the extreme cylinder pressures and thermal cycling common in high-performance Nissan RB-series builds. Constructed from multiple layers of embossed stainless steel, this gasket maintains a consistent torque set and provides a superior seal compared to traditional composite materials. The embossed outer layers act as a spring, conforming to the sealing surfaces of both the cylinder head and the exhaust manifold to effectively eliminate the risk of burn-through or gasket push-out.

This gasket features a technical .030-inch thickness and is designed for ports measuring 1.575 inches by 1.340 inches. Because the MLS design provides an active seal through mechanical tension, no additional liquid sealants or RTV are required for installation. This design requires less clamp load than standard gaskets, reducing potential bore distortion while ensuring a durable, leak-free exhaust path.

• Manufacturer Part Number: C4177-030
• Material: Multi-Layer Steel (MLS) with stainless shim layer
• Thickness: .030 inch
• Port Dimensions: 1.575 in x 1.340 in
• Installation: Dry-seal design (no sealants required)
• Durability: Corrosion resistant and burn-through resistant