GM TRUCKS 06259693 Van Cylinder Head 4.1L

( Brand: Gm Trucks ), ( Manufacturer Part Number: 06259693 ), ( Part Type: Cylinder Head ), ( Id: Ce5a737d-9b6b-4179-8fb9-8a807aa3fe27 ), ( Interchange: 306-722c ), ( Year: 1971 )

Review GM TRUCKS Chevy Van Cylinder Head Assembly Oem 4.1l fits G20 250 1967–1978

The **GM 06259693 cylinder head** for the **1967 1978 Chevrolet G20 4.1L (250ci) inline-six engine** is a meticulously crafted, high-performance component designed to restore or enhance the breathing and reliability of one of General Motors most iconic workhorse engines. This cast iron head, built to exacting specifications, features a **single-plane design** with **six intake and six exhaust ports**, each precisely machined to optimize airflow and combustion efficiency. The **250ci engine** known for its durability and versatility in everything from classic panel trucks and delivery vans to custom hot rods relies on this head to deliver smooth, torque-rich performance while maintaining its legendary longevity. The **valve seats** are precision-ground to ensure a tight seal, reducing blow-by and preventing premature wear, while the **combustion chamber shape** is optimized for improved compression and better fuel atomization, making it ideal for both stock and modified applications. Whether you're restoring a vintage G20 for daily driving, building a high-performance street rod, or repowering a classic van for modern use, this head provides the structural integrity and airflow necessary to keep the engine running strong for decades. Built to fit seamlessly with the **GM 250 s** proven pushrod architecture, it pairs effortlessly with modern upgrades like high-flow valves, performance cams, or even forced induction, making it a versatile choice for enthusiasts who demand both authenticity and performance. With its **durable cast iron construction**, **accurate porting**, and **OEM-compatible bolt pattern**, this cylinder head is the perfect blend of heritage and high-performance engineering for anyone looking to revive or redefine the legendary Chevrolet 250.

### **Pros and Cons of Buying a 1967 1978 Chevy G20 4.1L (250 CID) Cylinder Head (GM Part # 06259693)**

#### **Pros**

1. **Compatibility** This cylinder head is designed specifically for the **Chevy G20 (G-body) 4.1L (250 CID) inline-six engine**, which was used in many full-size trucks, vans, and some passenger cars from 1967 to 1978. It fits models like the **Chevy G20/G30/G40/G50**, **GMC Suburban**, **Chevy Suburban/Caprice**, and **Chevy Astro/Express vans**.

2. **Common Engine** The 250 CID inline-six was a widely produced engine, meaning parts are relatively accessible compared to rarer V8s or smaller blocks. This reduces long lead times for replacements.

3. **Simpler Design** Unlike modern high-performance heads, this is a **basic cast-iron pushrod head** with a single valve per cylinder (OHV design). While not high-performance, it is **easy to work on**, with straightforward valve springs, rocker arms, and pushrods.

4. **Budget-Friendly** Since this is a **common replacement part**, prices are generally reasonable compared to aftermarket or high-performance heads. A used or reconditioned head can often be found for **under $200 $400**, depending on condition.

5. **Repairable** Cracked heads can often be **welded or reconditioned** by a good machine shop. The design is forgiving compared to aluminum heads, which are more prone to catastrophic failure if cracked.

6. **Good for Basic Use** If you re running the engine for **daily driving, towing light loads, or a simple project**, this head will handle the workload without needing exotic materials or high-end machining.

7. **Aftermarket Support** There are **aftermarket cylinder heads** (like those from **Crane, Edelbrock, or Holley**) that improve performance, but the stock head is a **solid starting point** for restoration or basic use.

---

#### **Cons**

- **Warped or cracked heads** (especially from overheating or poor cooling).

- **Leaking valve cover gaskets** and **oil leaks** around the rocker arms.

- **Worn camshaft lobes** and **valve train wear** over time, leading to poor compression and power loss.

- **Porous casting** in some heads, which can cause **oil leaks** from the valve cover or oil passages.

2. **Poor Cooling Efficiency** The **single exhaust port per cylinder** design restricts airflow, leading to **lower efficiency and higher cylinder temperatures**. This can contribute to **pre-ignition (knocking)** if modified for higher performance.

3. **Limited Performance Potential** Even with a **new head**, the **stock 250 CID inline-six** is not a high-performance engine. It produces ** 120 150 HP** in stock form, which is **adequate for light towing but weak for heavy-duty use**. For better power, you d need:

- A **high-performance camshaft** (which may require head modifications).

- **Aftermarket cylinder heads** (like a **Crane or Edelbrock head**).

- **Forced induction** (turbo or supercharger), which is **not practical** with the stock head due to cooling limitations.

4. **Reliability Concerns** If the engine has **high mileage (over 200,000 miles)**, the **camshaft, lifters, and pushrods** may be worn, leading to **rough idle, misfires, or poor compression**. A **full rebuild** may be necessary before installing a new head.

5. **Hardware Compatibility Issues** If the engine has been **modified or rebuilt**, you may need to **match the head to the correct block and camshaft**. Mismatched components (e.g., a **high-lift cam with a stock head**) can cause **valve-to-piston contact** or **excessive valve float**.

6. **Environmental & Emissions Concerns** Older engines (pre-1975) often lack **modern emissions controls**, meaning they may **fail smog checks** in strict areas. If you re keeping the van for **daily use**, this could be a dealbreaker.

7. **Limited Longevity with Stock Modifications** If you plan to **modify the engine** (big valves, high-flow heads, forced induction), the **stock 250 CID inline-six is not a good platform**. It s better suited for **stock or mild performance builds**.

---

### **Ending Conclusion & Recommendation**

#### **When to Buy This Cylinder Head**

- You re **restoring a classic Chevy G20/G30 van or truck** and need a **budget-friendly replacement**.

- The engine is **low-mileage or has been recently rebuilt** with a **proven camshaft and valve train**.

- You re **not planning major performance modifications** just a **reliable, no-frills engine**.

- You have access to a **good machine shop** to **check for cracks, warp, and compression**.

- You re okay with **basic power** ( 120 150 HP) and **higher maintenance** than a modern engine.

#### **When to Avoid It**

- The engine has **high mileage (over 200K miles) without a full rebuild**.

- You plan **forced induction or aggressive modifications** this head is not built for it.

- You need **high reliability for daily driving** modern engines or a **rebuilt small-block Chevy V8** would be better.

- The van/truck is **used for heavy towing or performance driving** the 250 CID is weak for this.

- You re in an **area with strict emissions laws** and can t modify for compliance.

#### **Best Approach**

- **Cracks** (use dye penetrant or a magnetic particle inspection).

- **Warping** (lay it on a flat surface and check for gaps under a straightedge).

- **Valve seat wear** (should be smooth, not pitted).

- **Oil leaks** (check valve cover gasket and oil passages).

2. **Consider a Rebuilt or Aftermarket Head**

- If you want **better reliability**, look for a **rebuilt head from a trusted source** (e.g., **Chevy Specialty Parts, Summit Racing, or an engine rebuild shop**).

- If you want **more power**, a **Crane or Edelbrock cylinder head** (with matching camshaft) is a better long-term investment.

3. **Pair It with a Reliable Engine**

- If keeping the **250 CID inline-six**, ensure the **camshaft, lifters, and pushrods are in good condition**.

- If possible, **upgrade to a small-block Chevy V8** (305, 350, or LS swap) for **better power and reliability**.

4. **Budget for Maintenance**

- Expect **valve adjustments every 10K 15K miles** (unlike modern engines with hydraulic lifters).

- **Oil leaks** may require frequent gasket replacements.

- **Cooling system upgrades** (better radiator, thermostat housing) can help prevent overheating.

---

### **Final Recommendation**

- You re doing a **restoration project** on a classic G20/G30 van/truck **and** the engine is in **good condition**.

- You accept that it s a **basic, lower-performance engine** that requires **more maintenance** than modern alternatives.

- You **inspect it thoroughly** before purchase and **rebuild the engine properly** (cam, lifters, pushrods, seals).

- You need **reliability for daily use** or **heavy-duty applications**.

- You plan **aggressive modifications** (turbo, supercharger, big valves).

- You can t commit to **regular maintenance** (valve adjustments, oil leaks, cooling checks).

- A **rebuilt small-block Chevy V8 (305, 350, or LS swap)** for the van.

- An **aftermarket cylinder head (Crane, Edelbrock)** if staying with the 250 CID.

- A **modern diesel or turbocharged engine** if towing is a priority.

The **1967 1978 Chevy 250 CID inline-six is a character engine**, but it s **not the most practical choice** for modern or high-demand applications. If you re restoring a classic for **nostalgia and low-key use

Details:

Search for more parts CHEVY VAN 20 SERIES. Cylinder Head. CHEVROLET VAN 30 SERIES 75-78 6-292 4.8L. CHEVROLET VAN 30 SERIES 76-78 6-250 4.1L, w/o integral intake manifold.

part #: 06259693 price

• $675.00

specifications cylinderheapar:

• for models: G20, 250
• for makes: Chevy
• for years: 1967-1978
• brand: Gm Trucks
• mpn: 06259693
• part type: Cylinder Head
• id: Ce5a737d-9b6b-4179-8fb9-8a807aa3fe27
• interchange: 306-722c
• year: 1971

payments cylinderheapar:

• other
• credit card: Diners-club
• wallet: Google-pay

offer cylinderheapar:

• quantity: 1
• availability: In Stock
• options: Ship-to-home
• sold: 0
• started: April 16, 2026

shipping cylinderheapar:

• class: Standard
• transit: 4-7 Days
• service: Standard
• type: Fixed
• cost: $0.00

general cylinderheapar:

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

seller cylinderheapar:

• # reviews: 15843
• city: Brush, Colorado
• rating: 99.5%

returns cylinderheapar:

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

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