PONTIAC 12360340 Fiero Engine Cylinder Head 306-01664A 2.5L

( Manufacturer Part Number: 12360340 ), ( Type: Cylinder Head Assembly ), ( Ipn: 306-01664a ), ( Manufacturer Warranty: 1 Month )

Review PONTIAC Fiero 2.5l Engine Cylinder Head Assembly Oem fits 1987–1988

The **Pontiac 12360340 1987-1988 Fiero 2.5L Engine Cylinder Head** is a meticulously crafted, high-performance component designed specifically for the iconic mid-engined sports car that defined a generation. This cylinder head, manufactured to strict OEM specifications, represents the pinnacle of engineering for the Fiero s legendary **L41 2.5L inline-four engine**, which was renowned for its lightweight construction, high-revving nature, and aggressive performance. Crafted from precision-machined aluminum, the head features a compact yet robust design, incorporating four individual intake and exhaust ports that optimize airflow for maximum efficiency. The intake ports are contoured to promote smooth, high-velocity air flow into the combustion chambers, while the exhaust ports are engineered to minimize backpressure, ensuring that the engine s potent power delivery is fully realized. The head is equipped with **four valves per cylinder** (two intake and two exhaust), operated by a pair of overhead camshafts driven by a timing chain, allowing for precise valve timing and enhanced breathing at high RPMs. The combustion chambers are designed to promote efficient combustion, reducing knock sensitivity and enabling the engine to rev enthusiastically, a hallmark of the Fiero s driving experience. This cylinder head is compatible with both the **carbureted** and **fuel-injected** versions of the 2.5L engine, making it a versatile upgrade or replacement option for restorers, tuners, and performance enthusiasts seeking to restore or enhance their Fiero s legendary character. Whether used in a stock configuration for a faithful reproduction of the original driving dynamics or modified with performance upgrades like larger valves, high-flow heads, or forced induction, this cylinder head serves as the foundation for unleashing the full potential of the Fiero s mid-engine layout. Its durability and precision engineering ensure reliable operation under demanding conditions, making it an essential component for anyone aiming to preserve or amplify the spirit of this legendary sports car.

Buying a **Pontiac Fiero (1987-1988) 2.5L engine cylinder head** (part number **12360340**) involves several considerations, as this component is critical to engine performance and longevity. Below is a detailed breakdown of the pros and cons, followed by a conclusion and recommendation.

---

### **Pros of Buying a Replacement Cylinder Head**

1. **Restores Engine Performance**

The cylinder head is responsible for sealing combustion chambers, controlling airflow, and housing valves. A worn or damaged head can lead to poor compression, misfires, or loss of power. Replacing it with an OEM or high-quality aftermarket part can restore the engine to near-original specifications, improving acceleration, throttle response, and fuel efficiency.

2. **Prevents Further Engine Damage**

A failing cylinder head can cause catastrophic issues such as blown head gaskets, warped surfaces, or valve train damage. Addressing the problem early can save money by preventing more extensive (and costly) repairs, such as a full engine rebuild or replacement.

3. **Compatibility with Modifications**

If you plan to modify your Fiero (e.g., forced induction, high-performance camshafts, or increased compression ratios), a fresh cylinder head is often necessary to handle the additional stress. Stock heads may not be suitable for aggressive tuning without reinforcement or upgrading.

4. **OEM Quality (If Purchasing New or Authentic Replica)**

Original Pontiac cylinder heads (or high-quality replicas) are built to factory standards, ensuring proper fitment, valve train clearance, and sealing. This can be preferable if you prioritize reliability and longevity over cost savings.

5. **Increased Resale Value (If Restoring a Project Car)**

For a Fiero restoration, a new cylinder head signals to potential buyers that the engine has been properly maintained. This can justify a higher resale price, especially if the car is being sold as a complete project or show piece.

6. **Access to Upgraded Parts**

Some aftermarket cylinder heads offer improvements over the stock design, such as better cooling, reinforced construction, or compatibility with modern materials (e.g., aluminum with better heat dissipation). These can be beneficial for long-term durability.

---

### **Cons of Buying a Replacement Cylinder Head**

1. **High Cost Relative to the Fiero s Value**

The **Pontiac 12360340 cylinder head** (or an equivalent replacement) can cost between **$300 and $800**, depending on whether it s OEM, aftermarket, or a used/refurbished part. For a classic car like the Fiero whose overall value is often modest this represents a significant portion of the engine s cost. If the engine itself is severely worn or the car is a low-mileage project, the expense may not be justified.

2. **Labor-Intensive Installation**

Replacing a cylinder head requires disassembling the engine, removing the head, machining the mating surface (if warped), installing new gaskets, and reassembling with precision. This is a **multi-hour job** that demands mechanical skill. If you lack experience, labor costs at a shop can add **$500 $1,500 **, depending on the shop s rates and location.

3. **Potential for Hidden Issues**

- **Warped block decks** (requiring machining).

- **Cracked or corroded engine components** (e.g., intake manifold, oil passages).

- **Worn valve train** (sticks, guides, or springs may need replacement).

If these issues aren t addressed, the new head may fail prematurely or lead to recurring problems.

4. **Limited Aftermarket Support**

While some aftermarket cylinder heads exist for the Fiero, they are not as widely available as parts for more common engines. This can make sourcing, installation, and troubleshooting more difficult. OEM parts may be harder to find in good condition, increasing the risk of counterfeit or low-quality replicas.

5. **Risk of Overkill for Low-Mileage or Casual Use**

If the Fiero is a weekend driver with minimal miles and no performance ambitions, the benefits of a new cylinder head may not outweigh the costs. In such cases, a **head rebuild** (using the existing head with new internals and gaskets) could be a more economical alternative.

6. **Potential for Compatibility Issues**

If the cylinder head is not perfectly matched to the engine block (e.g., due to machining or modifications), issues like oil leaks, coolant mixing, or improper valve clearance can arise. This requires careful inspection and possibly additional machining work.

7. **Depreciation of Classic Car Parts**

Like many classic car parts, cylinder heads for the Fiero are not immune to depreciation. Even if you buy a "new" aftermarket part, its value may decline over time, especially if the Fiero market remains niche.

---

### **Conclusion**

Buying a replacement cylinder head for your **1987-1988 Pontiac Fiero 2.5L engine** is a **necessary investment if the head is failing or if you plan to modify the engine**. It restores performance, prevents further damage, and can be crucial for long-term reliability especially if the car is being tuned or restored to showroom condition.

However, the **high cost, labor requirements, and potential for hidden issues** make this a significant undertaking. If the cylinder head is the only failing component and the rest of the engine is in good shape, the expense may be justified. But if the engine is beyond repair or the car is a low-budget project, alternatives like a **head rebuild or engine swap** might be more practical.

---

### **Recommendation**

1. **Verify the Need**

Before purchasing, confirm that the cylinder head is indeed the root cause of your issues. Symptoms like **misfires, white smoke, overheating, or oil in the coolant** strongly indicate a failing head. A compression test or leak-down test can help diagnose the problem.

2. **Choose the Right Part**

- **OEM (Original Equipment Manufacturer):** Best for authenticity and reliability, but may be hard to find in good condition.

- **High-Quality Aftermarket:** Brands like **Eagle, JE, or Holley** offer reliable replicas. Ensure the part is designed for the Fiero s 2.5L engine.

- **Used/Refurbished:** Can be cheaper but carries risk. Inspect for cracks, warping, or signs of poor machining.

3. **Consider a Head Rebuild**

If the cylinder head itself is structurally sound but just needs new internals (valves, springs, guides, seals), a **head rebuild** from a specialist (e.g., **Valvematic, Summit Racing**) can cost **$200 $400** far less than a full replacement. This is ideal for low-mileage engines.

4. **Budget for Labor and Additional Work**

Account for **engine removal/installation, machining (if needed), and gasket replacement**. If the block is warped, expect to pay **$100 $300** for decking. Factor in **$500 $1,500** for professional labor if you lack the skills.

5. **Weigh the Car s Value and Intent**

- **For a project car or performance build:** A new cylinder head is worth the investment.

- **For a casual driver or low-budget restoration:** Prioritize other critical repairs (transmission, suspension, electrical) or consider a **used engine swap** from a known-good Fiero.

6. **Source from Reputable Sellers**

Purchase from **specialty classic car parts dealers, eBay (with verified sellers), or trusted mechanics**. Avoid "too good to be true" deals, as counterfeit or damaged parts can cause more harm than good.

7. **Document the Process**

Keep records of the work done, parts used, and any modifications. This helps with future troubleshooting and resale value if you decide to sell the car later.

---

### **Final Verdict**

- The head is confirmed faulty and the rest of the engine is sound.

- You plan to modify the engine or restore the car to high standards.

- You have the budget for labor and potential additional repairs.

- The engine is beyond repair or the car is a low-priority project.

- You lack the mechanical skill or tools to install it properly.

- The cost exceeds the car s value or your budget for the project.

For most **1987-1988 Fiero owners**, a **new or rebuilt cylinder head is a smart investment** if the engine is the focus of the restoration. However, always approach the repair with a clear plan for the entire engine and consider whether the car s overall condition justifies the expense.

Details:

1987 1988 PONTIAC FIERO 2.5L ENGINE CYLINDER HEAD ASSEMBLY 12360340 OEM. CELEBRITY 87-88 4-151 2.5L. 6000 87-88 4-151 2.5L. CENTURY 87-88 4-151 2.5L.

part #: 12360340 price

• $349.99

specifications cylinderheapar:

• for makes: Pontiac
• for years: 1987-1988
• mpn: 12360340
• type: Cylinder Head Assembly
• ipn: 306-01664a
• manufacturer warranty: 1 Month

returns cylinderheapar:

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

general cylinderheapar:

• condition: Used
• Car Truck Parts Accessories > Engines Engine Parts > Cylinder Heads

payments cylinderheapar:

• credit card: Mastercard
• other
• wallet: Apple-pay

seller cylinderheapar:

• rating: 100.0%
• city: Houston, Texas
• # reviews: 68291

offer cylinderheapar:

• quantity: 1
• options: Ship-to-home
• sold: 0
• availability: In Stock
• started: March 3, 2026

shipping cylinderheapar:

• type: Fixed
• transit: 2-6 Days
• class: Standard
• service: Standard
• cost: $0.00

Pontiac 12360340 Is Similar To:

• 4x-1h Pontiac Cylinder Heads (44% similar) Rebuilt, ready for final cleaning and installation. Good street heads for low-to-medium compression pump-gas engine. New street valve job with wide seats for flow and durability. Stamped 1h in the vertical boss see photos. Push rod guide plates included and installed. Deck resurfaced to a true flat ...(April 8th, 2018)
• 4x-7 4x-7 Pontiac Cylinder Heads (42.3% similar) 11 intake, 66 exhaust. Vatted and . Bare heads only, valves, springs, rockers, and related Howe not included. Rocker studs are press fit. Good street heads for medium compression pump-gas engine. As-cast chamber volume is 98CC. Both heads cast on day shift. Originally used on 200HP...(July 26th, 2017)
• 10000187 General Motors Nos Gm Chevrolet Buick Oldsmobile Pontiac Engine Gasket (24% similar) You are buying on exactly what is pictured. Please also listings for thousands more nos parts available immediate purchase. Nos stripes, decals, electrical and mechanical parts important. When you homepage just enter the year, make and or model of your vehicle in search bar. These are very rare to ...(April 4th, 2018)
• 10118604 General Motors Nos Gm Chevrolet Buick Oldsmobile Pontiac Cadillac Head (20% similar) The part number is group. If you are out of the country please understand this while buying on item. Nos stripes, decals, electrical and mechanical parts important. Please also listings for thousands more nos parts available immediate purchase. When you homepage just enter the year, make and or ...(April 6th, 2018)
• 11569648 Gm Cylinder Head Bolt Lot Of Chevy Buick Olds Pontiac (36.1% similar) God bless the USA and her troops. Sales and shipping within the USA only. The winning bidder will receive all 10 pieces. They're nos in the original packaging. I do not know any of the exact applications. Please visit my other offer offerings for more quality stuff. Offered is a believed to fit some...(January 2nd, 2019)
• 1378939 24 Nos 1964-81 Pontiac Head Bolts Gto Judge Trans Am 350 400 421 428 455 (22.5% similar) These were used in several gm products as well as years. Part no buying on 24 nos pontiac head bolts...(December 7th, 2015)
• Skylark Oldsmobile 80-88 Phoenix Nos Buick Fiero Omega Chevy Pontiac 14090561 Citation (21.7% similar) Nos Chevy Buick Oldsmobile pontiac citation skylark phoenix omega fiero...(March 21st, 2015)
• 50-54 1937-1949 Pontiac High Compression Cylinder Head (40% similar) It has the 2 ratio. Comes with nos head gasket. This will also fit the engines. Here I have a good used high compression cylinder head for pontiac 8 cylinder engines. God bless America. Buyer to pay good luck buying...(January 24th, 2016)
• 518794 1949-1952 Pontiac Straight 8 Engine Motor Cylinder Head Rat Rod Hot (45.5% similar) TRPOWCOAT45 store's will enhance your listings. Please with any issues before starting a claim through...(February 2nd, 2016)
• Buick Pontiac Olds 93-05 95 24573310 Lot 93 5 97 Head Chevy 94 96 Bolts 9 Gm (36.7% similar) Out of a local estate. Bag is beat up a bit...(March 26th, 2015)
• 4-barrel 1972 Gto Heads Cylinder Pontiac 455 Original 400 7k3 Gm 72 Firebird (32.7% similar) 2 Cr on a 400 and approx these are these have been cleaned and cracked checked OK. No valves, springs or hardware is included. 5 on a 455 as cast. They are made with hardened valve seats. They can be milled for more. These have the small exhaust crossover so leaks in this location won't be a problem...(June 11th, 2015)