PORSCHE 9301043412R Cylinder Heads Plug Engine Block 935

( Manufacturer Part Number: 9301043412R ), ( Type: Cylinder Head ), ( Performance Part: Yes )

Review PORSCHE 935 Cylinder Heads Plug Engine Block fits TWIN TURBO 1978–1979

The **Porsche 9301043412R cylinder heads** are meticulously crafted, high-performance components designed exclusively for the legendary **935 twin-plug turbocharged engine** from the 1978 and 1979 model years. These heads are a direct replacement for the original **9301043412** units, ensuring perfect compatibility with the iconic **3.0L flat-six turbocharged engine block** that powers the 935 s legendary racing heritage. Engineered with precision, these heads feature **cast aluminum construction** reinforced with **high-strength alloys** to withstand the extreme pressures and temperatures generated by the twin-plug ignition system and forced induction. The **intake and exhaust ports** are optimized for superior airflow, maximizing volumetric efficiency and torque delivery while maintaining the engine s signature **smooth, linear power curve** a hallmark of Porsche s engineering excellence. The **turbocharged application** demands robust sealing and cooling, which these heads deliver through **high-quality gaskets, precision-machined valve seats, and efficient cooling passages** that prevent overheating under sustained boost conditions. Whether restoring a classic 935 for track use or preserving its original performance for concours display, these cylinder heads are built to meet the exacting standards of Porsche s racing pedigree, ensuring reliable operation, enhanced breathing, and the unmistakable growl of a properly tuned turbocharged flat-six. Each set is thoroughly inspected for quality, with **newly machined valve guides, seats, and ports** to eliminate wear and improve performance, making them an ideal choice for both purists and performance enthusiasts seeking to revive or refine their 935 s legendary power delivery.

### **Pros and Cons of Buying Porsche 930/935 Cylinder Heads (Part Number 9301043412R) for a 1978 1979 Twin-Plug Turbo Engine Block**

1. **Performance Potential** These cylinder heads are designed for the 935 s high-revving, turbocharged 3.0L engine, which means they can support significant power gains when paired with a properly tuned turbo setup. The twin-plug design improves combustion efficiency, especially under forced induction.

2. **Stock Compatibility** The part number (9301043412R) is a direct replacement for the original 935 heads, meaning they will bolt onto a 1978 1979 twin-plug block without major modifications. This reduces the risk of clearance issues with the turbo, intake, or exhaust.

3. **Durability** Porsche 935 cylinder heads are built to withstand high stress, including the thermal and mechanical loads of turbocharging. The forged construction and robust valve springs make them more durable than aftermarket alternatives in some cases.

4. **Aesthetic & Historical Value** Restoring the original heads preserves the authenticity of the car, which is important for enthusiasts who prioritize period-correct builds. They also add to the car s collectible appeal, especially if the engine is being returned to showroom condition.

5. **Potential for Future Modifications** If you plan to upgrade the turbo or intake later, these heads provide a solid foundation. They can accommodate larger valves (up to a point) and better flow than some aftermarket options, though porting and polishing may still be necessary for maximum performance.

6. **Easier to Source Gaskets & Parts** Since these are original Porsche components, finding OEM gaskets, valve seals, and hardware is straightforward compared to aftermarket alternatives that may require special ordering.

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1. **Cost** Original Porsche cylinder heads are expensive, often priced between **$2,500 $4,500 ** depending on condition, rarity, and whether they come with the block. This can be a significant investment for a project car, especially if other components (turbo, intake, fuel system) also need upgrading.

2. **Condition & Availability** Finding a set in good condition can be difficult. Many original heads have been modified or are in poor shape due to age, warping, or internal damage. You may need to inspect them closely for cracks, warpage, or worn valve guides/seats.

3. **Weight** These heads are heavy (around **20 25 lbs each**), which adds to the rotating mass of the engine. While not a major issue for a 935, it s something to consider if you re pushing for extreme high-RPM performance.

4. **Maintenance Requirements** Original heads may require **porting, polishing, and valve job** to achieve modern performance levels. Even if they look good, internal wear (valve guides, seats, springs) can limit longevity unless restored properly.

5. **Turbo & Fuel System Dependencies** Simply bolting on original heads won t guarantee power gains without a matching turbo (e.g., KKK, Garrett, or a modern aftermarket unit), upgraded fuel system (pump, injectors, or fuel rail), and proper tuning. Ignoring these will lead to detonation, poor performance, or engine damage.

6. **Potential for Warpage** Over time, cylinder heads can warp from heat cycles. Even if they look straight, a **warpage check** (using a straightedge and feeler gauges) is essential before installation. Severe warpage may require machining or replacement.

7. **Limited Modern Support** Unlike aftermarket heads, these are no longer produced by Porsche. If something fails, finding replacement parts or a specialist to work on them may be harder than with more common engine components.

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### **Conclusion & Recommendation**

- You prioritize **authenticity and historical accuracy** over raw performance.

- You re willing to invest in a **high-quality, period-correct restoration**.

- You have the budget to **supplement them with necessary upgrades** (turbo, fuel system, porting).

- You re prepared to **inspect them thoroughly** for condition and warpage before purchase.

However, if your primary goal is **maximum power at the lowest cost**, aftermarket heads (e.g., **Comp Cams, JE, or forged aluminum options**) may offer better value, especially if you plan aggressive modifications. Aftermarket heads can often be **ported, polished, and upgraded more easily** and are generally more affordable.

- **If restoring a showroom 935 or keeping it period-correct** **Original heads are the best choice**, provided you find a clean set and pair them with a **modern turbo and fuel system**.

- **If building a high-performance street/race car** **Consider aftermarket heads** (e.g., **Comp Cams 935 heads or forged aluminum options**) for better flow, lighter weight, and easier modifications.

- **Always get a professional inspection** before purchasing, as warpage, cracks, or internal wear can ruin the heads if ignored.

Would you like guidance on where to source these heads or what other components to pair them with?

Details:

Up for sale is an original set of rare Twin plug Porsche 934/935 cylinder race heads. Any questions let me know. Also comes with original Bosch Spark plugs never opened box, still in wrapper.

part #: 9301043412r price

• $9500.00

specifications cylinderheapar:

• for models: Turbo, Twin
• for makes: Porsche
• for years: 1978-1979
• mpn: 9301043412r
• type: Cylinder Head
• performance part: Yes

shipping cylinderheapar:

seller cylinderheapar:

• # reviews: 712
• city: Miami, Florida
• rating: 98.5%

returns cylinderheapar:

• policy: No Returns

general cylinderheapar:

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

offer cylinderheapar:

• started: April 21, 2026
• best offers: True
• sold: 0
• availability: In Stock
• quantity: 1
• options: Seller-arranged-local-pickup

payments cylinderheapar:

• other
• wallet: Paypal
• credit card: Discover

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