1. Exhaust & Emission Parts To Buy
  2. sku: 20566329923542722
  3. CHEVROLET CORVETTE

CHEVROLET 331.GM1Z63 Outlet Exhausts Manifold 63-67 2.5

fits model: Corvette. make: Chevrolet. year: 1963.

331.gm1z63 Chevrolet 63-67 Corvette Side Outlet Exhausts With 2.5 Inch Manifold Oem

( Part Type: Outlet Exhaust Manifold ), ( Conditions Options: Side Outlet Exhausts Manifold ), ( Genuine Oem: Yes ), ( Ipn: 331.gm1z63 )

Review CHEVROLET Side Outlet Exhausts 2.5 Inch Manifold Oem fits CORVETTE 1963

The **Chevrolet 331 GM1Z63 1963 1967 Corvette Outlet Exhaust Manifold (2.5-inch)** is a meticulously crafted, high-performance component designed to enhance the breathing and efficiency of the legendary **327/350 cubic-inch small-block Chevrolet V8** found in the first-generation Corvette. This manifold serves as the critical junction between the engine s exhaust ports and the exhaust headers, playing a pivotal role in optimizing exhaust flow while maintaining structural integrity under the high-stress conditions of high-performance driving. Crafted from **high-quality cast iron**, this manifold is engineered to withstand the extreme heat and pressure generated by the aggressive exhaust pulses of the Corvette s iconic engine, ensuring durability and longevity even under heavy acceleration or high-RPM operation. The **2.5-inch outlet diameter** strikes a balance between unrestricted exhaust flow and compatibility with modern or aftermarket headers, allowing for a smooth transition from the manifold to the exhaust system without unnecessary restrictions. Whether paired with factory headers, high-flow aftermarket headers, or a full exhaust system, this manifold is a direct replacement for the stock unit, ensuring a seamless fitment with minimal modifications required. Ideal for both restoration projects and high-performance builds, this component is a must-have for enthusiasts seeking to improve exhaust scavenging, reduce backpressure, and enhance overall engine efficiency all while preserving the classic aesthetic and mechanical integrity of the **C1 Corvette**.

### **Pros and Cons of Buying a Chevrolet 331.GM1Z63 (1963-1967 Corvette) Outlet Exhaust with a 2.5 Manifold**

#### **Pros**

1. **Performance Gains** The 331.GM1Z63 engine is a high-performance small-block Chevy, and upgrading to a Corvette-style outlet exhaust and 2.5 manifold can improve exhaust flow, reducing backpressure. This can lead to better horsepower and torque, especially at higher RPMs.

2. **Classic Corvette Sound** The outlet exhaust system is designed to replicate the deep, aggressive exhaust note of the original Corvette engines, which many enthusiasts find desirable for both street and track use.

3. **Improved Exhaust Scavenging** The 2.5 manifold is a high-performance alternative to the stock 2-barrel manifold, offering better cylinder head flow and improved exhaust gas evacuation. This can enhance engine breathing and responsiveness.

4. **Compatibility with Modifications** If you plan to further modify the engine (e.g., headers, carburetor upgrades, or forced induction), this exhaust and manifold setup provides a solid foundation for those upgrades.

5. **Aesthetic Appeal** The Corvette-style exhaust system enhances the classic look of the 331 engine bay, making it more visually appealing for show or street use.

6. **Durability** Properly installed, these components are built to handle the demands of a high-performance engine, especially if paired with a supporting drivetrain.

7. **Aftermarket Support** There is a strong aftermarket presence for these parts, meaning you can find supporting components (gaskets, clamps, exhaust headers) if needed.

---

#### **Cons**

1. **Cost** High-quality outlet exhaust systems and 2.5 manifolds are not cheap. Depending on the brand and materials, you could spend several hundred dollars, which may be a significant investment for a classic engine.

2. **Installation Complexity** Installing a Corvette-style outlet exhaust requires careful attention to fitment, gasket sealing, and alignment. Improper installation can lead to leaks, exhaust noise, or even engine damage if components are misaligned.

3. **Potential for Leaks** The 2.5 manifold and outlet exhaust system rely on gaskets and clamps for sealing. Over time, these can degrade, leading to exhaust leaks that can be difficult to diagnose and fix.

4. **Backfire Risk** If the exhaust system is not properly tuned or if there are leaks, you may experience backfires, especially when revving the engine or shifting gears.

5. **Weight Considerations** While not overly heavy, the exhaust system adds some weight to the engine bay, which may slightly impact drivability or handling in a lightweight classic car.

6. **Compatibility Issues** Not all 331 engines are identical, and fitment can vary slightly depending on the year and modifications. Ensuring a perfect match is crucial to avoid performance or reliability issues.

7. **Maintenance Requirements** Like any high-performance exhaust system, this setup may require more frequent inspections for leaks, rust, or wear, especially if driven in harsh conditions.

---

### **Conclusion**

The **Chevrolet 331.GM1Z63 Corvette outlet exhaust with a 2.5 manifold** is an excellent upgrade for enthusiasts looking to enhance the performance, sound, and appearance of their small-block Chevy engine. The benefits in terms of exhaust flow, power, and classic styling are significant, and the aftermarket support ensures reliability if installed correctly.

However, the cost, installation complexity, and potential for leaks or backfires must be carefully considered. If you are willing to invest the time and money into a proper installation and maintenance plan, this upgrade can be highly rewarding. For those on a tighter budget or with less experience in engine modifications, it may be wise to start with simpler upgrades (e.g., headers or a carburetor swap) before committing to this system.

### **Recommendation**

If you are running a **331 engine in a classic Corvette or a similar application** and want to maximize performance while maintaining the iconic exhaust tone, this is a strong choice. Ensure you:

- Use high-quality gaskets and clamps.

- Have a mechanic with experience in small-block Chevy exhaust systems perform the installation.

- Consider pairing it with supporting modifications (e.g., headers, a performance carburetor, or a tune if using fuel injection).

- Regularly inspect for leaks, especially after initial break-in.

For **street-driven daily drivers**, this upgrade is excellent if you prioritize sound and performance. For **track or high-RPM use**, it can be even more beneficial, but ensure the rest of the drivetrain (transmission, rear end, etc.) is up to the task.

If you are unsure about installation or maintenance, consult with a trusted mechanic or exhaust specialist before purchasing. Otherwise, this is a **highly recommended upgrade** for the right project.

Details:

SIDE OUTLET EXHAUSTS W/2.5 MANIFOLD.

specifications emissyste:

  • for models: Corvette
  • for makes: Chevrolet
  • for years: 1963
  • part type: Outlet Exhaust Manifold
  • conditions options: Side Outlet Exhausts Manifold
  • genuine oem: Yes
  • ipn: 331.gm1z63

returns emissyste:

  • paid by: Buyer
  • time: 30 Days
  • policy: Returns Accepted

general emissyste:

  • Car Truck Parts Accessories > Exhaust Emission Systems > Exhaust System Kits
  • condition: Used

seller emissyste:

  • rating: 99.4%
  • city: Rancho Cordova, California
  • # reviews: 9871

shipping emissyste:

  • class: Standard
  • cost: $0.00
  • transit: 5-12 Days
  • service: Standard
  • type: Fixed

offer emissyste:

  • availability: In Stock
  • sold: 0
  • started: March 6, 2026
  • best offers: True
  • quantity: 1
  • options: Ship-to-home

payments emissyste:

  • wallet: Apple-pay
  • credit card: Visa
  • other
for models: corvette, for makes: chevrolet, for years: 1963, part type: outlet exhaust manifold, conditions options: side outlet exhausts manifold, genuine oem: yes,
manufacturer: chevrolet, category: auto parts > car truck parts accessories > exhaust emission systems > exhaust system kits, sku: 20566329923542722,
Chevrolet Is Similar To:
emissyste logo
1 offer $285.77 USD
  • Used. Offer #1 priced at $285.77 + $0.00 shipping estimate = $285.77* total. SIDE OUTLET EXHAUSTS W/2.5" MANIFOLD 63-67 Chevrolet Corvette Side Outlet Exhausts W/ 2.5" Manifold OEM.FREE SHIPPING

Copyright © emissyste.com