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The debate between LS and HEMI engines has been a long-standing topic among automotive enthusiasts. Both engine families have their unique characteristics, strengths, and weaknesses. In this article, we will compare the two platforms, focusing on building a 600+ horsepower street machine with forged internals.
Understanding LS and HEMI Engines
The LS engine family, developed by General Motors, is known for its lightweight design and high performance. The HEMI, produced by Chrysler, is renowned for its distinctive combustion chamber design and power delivery. Both engines can be built to produce impressive horsepower figures, but they have different approaches to achieving performance.
LS Engine Overview
LS engines are part of GM’s Gen III and IV small-block family. They are known for their:
- Aluminum or iron block options
- High-revving capabilities
- Wide aftermarket support
- Efficient fuel injection systems
HEMI Engine Overview
HEMI engines utilize a hemispherical combustion chamber design, which allows for better airflow and combustion efficiency. Key features include:
- Robust iron block construction
- High torque output
- Unique design for better thermal efficiency
- Strong performance in both street and race applications
Building a 600+ HP Street Machine
To achieve 600+ horsepower from either engine, several components must be upgraded. Below are the critical areas to focus on for both LS and HEMI builds.
Forged Internals
Forged internals are essential for handling the increased power and stress associated with high horsepower builds. Consider the following:
- Forged pistons for durability
- Forged connecting rods for strength
- Forged crankshafts to withstand high RPMs
Performance Upgrades
In addition to forged internals, several performance upgrades are necessary to reach the desired horsepower levels:
- High-performance camshaft for better airflow
- Upgraded cylinder heads for increased power
- High-flow fuel injectors to support increased fuel needs
- Aftermarket intake manifold for improved performance
- Forced induction options (supercharger or turbocharger)
Comparative Analysis: LS vs HEMI
When comparing the LS and HEMI engines for building a 600+ HP street machine, several factors come into play:
Weight and Size
The LS engine is typically lighter than the HEMI, which can lead to better handling characteristics in a street machine. This weight advantage can be significant in performance applications.
Power Delivery
HEMI engines are known for their strong low-end torque, making them ideal for street applications where immediate power is desired. LS engines, while they can produce impressive torque, often excel in high-rev situations.
Aftermarket Support
The LS platform has a vast aftermarket support network, providing numerous options for performance parts and upgrades. While the HEMI also has a growing aftermarket, it may not be as extensive as that of the LS.
Conclusion
Both LS and HEMI engines can be built to produce over 600 horsepower, but they cater to different preferences and performance characteristics. The choice ultimately depends on the specific goals of the builder, whether it be weight, power delivery, or aftermarket support. Regardless of the choice, building a high-powered street machine is an exciting venture for any automotive enthusiast.