Plenum Top Hi-Ram 95mm

The Holley Plenum Top Hi-Ram 95mm is a high-performance intake manifold designed for serious LS-series engine builders and performance enthusiasts who demand maximum airflow and tuning flexibility. Built on the proven tunnel ram platform, this plenum assembly bridges the gap between street and competition applications where intake velocity and manifold runner optimization directly impact horsepower delivery. Whether you're building a street machine, bracket racer, or high-output truck platform, this component provides the foundation for aggressive induction tuning and responsive throttle response.

Manufactured from aluminum for weight savings and thermal efficiency, the Plenum Top Hi-Ram 95mm features a 95mm throttle body flange that accepts modern fuel injection systems while maintaining the flow characteristics of traditional tunnel ram designs. The natural aluminum finish allows for easy custom finishing and anodizing if desired, while the proven hi-ram geometry accelerates intake charge velocity through optimized plenum volume. This design reduces reversion losses and supports the high RPM power bands critical to street and strip performance, making it compatible with GM LS-series engines across all displacement variants from the 5.3L to the 7.0L.

Installation requires proper fuel rail configuration, carb spacer compatibility, and manifold gasket selection—consult your engine builder or tuner to confirm manifold runner alignment with your specific cylinder head. Weighing 9.81 pounds, this plenum top pairs with compatible fuel injection harnesses, throttle bodies, and intake runners to complete your induction system. Performance gains are maximized when tuned with matched fuel delivery, ignition timing, and engine management calibration for your target horsepower level.