In the fast world of high-performance LS3 engines, the chase for increased power and better airflow has driven enthusiasts to build monsters with aftermarket upgrades. A crucial component that can significantly improve engine performance is your intake manifold. In this article, we delve into the realm of high rise intake manifolds for LS3 engines, exploring options from fabricated aluminium sheet constructions to cast aluminium varieties, with a focus on budget-friendly alternatives to the Holley Hi Ram.

The Evolution of LS3 Intake Manifolds:

As LS3 engines and LS swaps continue to dominate the high-performance scene, enthusiasts are constantly seeking ways to extract more power from these powerhouses. The intake manifold plays a pivotal role in this pursuit, serving as the gateway for air to enter the engine and mix with fuel. High rise intake manifolds, in particular, are designed to optimise airflow at higher RPMs, providing a noticeable boost in horsepower and torque.

Fabricated Aluminium Sheet Intake Manifolds:

One option that has gained popularity among LS3 enthusiasts is the fabricated aluminium sheet intake manifold. Crafted from high-quality aluminum sheets, these hi ram intake manifolds offer a lightweight yet robust solution for those looking to reduce overall engine weight while maintaining durability. The fabrication process allows for intricate design customisation, enabling tuners to tailor the manifold to specific performance needs.

The appeal of fabricated aluminium sheet intake manifolds extends beyond their weight and customisation advantages. Their smooth internal surfaces promote better airflow, optimising the air-fuel mixture for improved combustion efficiency. Additionally, the heat dissipation properties of aluminium aid in temperature regulation, preventing heat soak and ensuring consistent performance under demanding conditions.

The Velocity Fabricated Aluminium LS3 Intake Manifold is the choice for NA and forced induction performance for your LS3 L98. The intake runners are velocity stacked which provides higher air-speed over plain tubes. The design is suited to vehicles where height is not a restriction such as race applications.

Cast Aluminium Intake Manifolds:

On the flip side, cast aluminium intake manifolds present a different approach to enhancing LS3 engine performance. Cast as a single piece, these manifolds boast structural integrity and durability. While they may be heavier than their fabricated counterparts, cast aluminium intake manifolds offer a distinct advantage in terms of simplicity and ease of installation.

Our cast aluminium Velocity LS3 / L92 Hi-Ram Intake Manifolds exemplify the importance of design in EFI performance. With a large plenum and long intake runners, these manifolds are crafted for maximum power generation. Hi-Ram intakes can elevate the rpm powerband on LS3 engines to an impressive 7,000 to 8,000 rpm, maintaining torque at lower RPMs for a well-rounded performance.

EFI Performance and Intake Manifold Design:

In the old days, carburetors dictated engine performance, with intake manifold design influencing signal strength and runner dynamics. In our modern technological era, while carburetors remain useful, EFI and computer-controlled engine management systems are increasingly popular. Yet, even in EFI, particularly port fuel injection, the design of the intake manifold continues to play a vital role.

Addressing skeptics who question the significance of intake manifold design in EFI, it's essential to recognise that fuel injection occurs near the end of the runner, under pressure. Despite this, factors like plenum volume, runner length, and overall design contribute to enhanced combustion efficiency, power delivery, and throttle response in EFI systems.

Considerations for Hi-Ram Intake Manifolds:

While the performance gains of the Hi-Ram are undeniable, it's essential to address practical considerations. Standing at 12 inches tall, the Velocity LS3 / L92 Hi-Ram Intake Manifold may pose hood clearance challenges for some vehicles. However, the aggressive aesthetics and substantial power gains make it a compelling choice for enthusiasts willing to make a bold statement, perhaps even cutting a hood vent for installation.

Intake Manifold Design in EFI vs Carbureted Engines:

In conclusion, the age-old principles that governed intake manifold design in carbureted engines continue to be relevant in our EFI-driven world. The choice of intake manifold remains a critical decision, influencing performance characteristics across different engine setups. Whether running carburetors or EFI, the importance of selecting an intake manifold for peak power vs torque comes down choosing your intake to make the most of your engine where it serves you best.