fits model: 340, 318. make: Chrysler, Mopar, Dodge.

( Brand: Dodge ), ( Manufacturer Part Number: 2658278 ), ( Part Type: Crankshaft ), ( Material: Steel ), ( Vintage Part: Yes )
The **Dodge 2658278 340 Chrysler Mopar Forged Steel Crankshaft (010/.010 318)** is a high-performance, precision-engineered component designed to deliver exceptional durability, reliability, and power for high-output applications in muscle cars, street rods, and performance builds. Crafted from **full-forged 4340 alloy steel**, this crankshaft is built to withstand extreme stress, high RPMs, and aggressive engine modifications without compromising structural integrity. The **010/.010 journal configuration** featuring 0.750-inch main journals and 0.625-inch rod journals strikes an ideal balance between strength and weight, making it well-suited for engines with moderate to high displacement, such as the legendary **318 cubic-inch small-block Chrysler** found in classic Dodge and Plymouth models. The **7-bearing design** ensures smooth operation and optimal oil flow, reducing friction and minimizing wear, while the **precision-machined counterweights** help maintain perfect balance, reducing vibration and enhancing longevity.
This crankshaft is engineered to support **high-performance applications**, including forced induction (turbocharged or supercharged) setups, nitrous oxide enhancements, and aggressive camshaft selections, making it a versatile choice for both street and track use. The **Mopar brand** guarantees quality craftsmanship, with each crankshaft undergoing rigorous inspection to meet or exceed factory specifications, ensuring a seamless fit with stock or aftermarket components. Whether you're restoring a classic **Dodge 340** or building a modern high-performance engine, this crankshaft provides the **strength, precision, and reliability** needed to handle the demands of modern tuning. Its **forged construction** eliminates the risk of fatigue failure, while the **smooth finish and precise tolerances** ensure optimal performance across a wide range of engine modifications. Upgrade your engine with this **Mopar forged steel crankshaft** and experience the confidence of knowing your powerplant is built to last.
### **Pros and Cons of buying a Dodge 2658278 340 Chrysler Mopar Forged Steel Crankshaft (010/.010, 318)**
#### **Pros:**1. **High-Quality Material** The forged steel construction ensures durability and resistance to stress, making it suitable for high-performance applications. Forged cranks are less prone to cracking or warping compared to cast counterparts.
2. **Balanced Fitment** The 010/.010 rod journal spacing is compatible with a wide range of Chrysler V8 engines, including the 340, 360, and 440 series, as well as aftermarket builds. This makes it a versatile choice for restorations or modifications.
3. **Proven Performance** Mopar (Chrysler s original equipment) parts are designed to meet factory specifications, ensuring reliability in stock and modified applications. Forged cranks are often preferred in forced-induction builds due to their strength.
4. **Compatibility with Aftermarket Upgrades** Since this crank is designed for a 318-inch displacement (though it can be used in larger engines with proper rod length adjustments), it pairs well with stroker kits, big-block swaps, or high-performance camshafts.
5. **Warranty and Support** Mopar parts typically come with manufacturer-backed warranties, providing peace of mind against defects. Chrysler/Mopar dealerships and specialty shops can offer installation support.
6. **Better Weight Distribution** Forged cranks are often lighter than cast equivalents, which can improve engine balance and reduce reciprocating mass, aiding in high-RPM performance.
7. **Long-Term Reliability** Forged steel cranks are less likely to fail under extreme stress, making them ideal for daily drivers, muscle cars, or classic restorations where longevity is critical.
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#### **Cons:**1. **Cost** Forged steel cranks are significantly more expensive than cast alternatives. The price reflects the superior material and machining process, which may be a barrier for budget-conscious buyers.
2. **Specialized Installation** Some builds may require rod length adjustments or main cap modifications to ensure proper fitment, especially when using it in non-native engine configurations (e.g., a 340 crank in a 426 Hemi block). This may necessitate additional machining or custom parts.
3. **Limited Availability** While Mopar parts are widely available, specific forged cranks (especially older or discontinued models) may require ordering from specialty suppliers, which could extend lead times.
4. **Potential Overkill for Stock Applications** If the engine is not heavily modified (e.g., no forced induction, mild camshafts, or stock compression), a forged crank may be unnecessary, making a cast crank a more cost-effective choice.
5. **Maintenance Considerations** Forged cranks require proper lubrication and maintenance to prevent wear on rod bearings or main journals. Neglecting oil changes or using low-quality oil can compromise performance.
6. **Weight vs. Power Tradeoff** While forged cranks are lighter than cast, some aftermarket forged cranks (especially those with aggressive machining) may sacrifice some strength for weight savings. Always verify the crank s specifications to ensure it meets your power goals.
7. **Compatibility with Non-Standard Engines** If the engine is heavily modified (e.g., stroker rods, custom blocks), the crank may need additional machining or balancing, adding to costs.
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### **Conclusion:**The **Dodge 2658278 340 Mopar forged steel crankshaft (010/.010, 318)** is an excellent choice for **high-performance, modified, or restored Chrysler V8 engines**, particularly those running forced induction, big cams, or stroker kits. Its forged construction ensures reliability under stress, and its versatility makes it suitable for a range of builds. However, the **higher cost and potential need for additional machining** may not justify its purchase for stock or lightly modified engines.
If your project involves **serious power goals, forced induction, or a classic restoration where durability is critical**, this crank is a strong recommendation. For **stock or mildly modified engines**, a cast crank may suffice and save money without sacrificing performance.
### **Recommendation:**- **Buy it if:** You re building a **high-performance, stroker, or forced-induction engine** in a Chrysler V8 (340, 360, 440, etc.), or restoring a classic muscle car where longevity is a priority.
- **Skip it if:** Your engine is **stock or mildly modified**, and you re on a tight budget opt for a cast crank instead.
- **Consider alternatives if:** You need a crank for a **non-standard displacement** (e.g., 426 Hemi) or require **custom machining**, as compatibility may vary.
For the best results, consult with a **reputable engine builder or Mopar specialist** to ensure proper fitment and installation.
Used factory forged crankshaft for Dodge 340 with casting numbers 2658278, Main journals measure 2.490 .010, and rod are 2.115 please look at all pics condition.