This is a complete bolt-on intake manifold kit for any Gen-3, cathedral port LS/Vortec series engine. This kit not only improves the look of your engine bay but also increase horsepower and torque.
Tested up to 23psi boost on a Vortec 6.0 with hot cam, and 75lb injectors, this setup (102mm, high ram) made over 35hp gains when compared to a stock LS1 intake manifold.
High-Rise (9" Height): Recommended for LS / Vortec with larger displacement and high horsepower / forced induction. Our High profile design has a bold appearance and maximizes horsepower in the higher end, and much more consistent torque levels throughout the power band. Please check your hood clearance before you purchase.
Low-Rise (xx" Height): Virtually the same height as an OEM LS1 style intake. This manifold has increased torque and horsepower levels over stock throughout the entire power band. Recommended for low clearance hoods and N/A engine builds. (Also tested at 23psi boost).
This Fuel Rail Kit allows you to run Vortec LS6 and LS1 style injectors. Increased rail size with more flow and capacity over OEM. All fittings and hardware included.
*Does not fit OEM manifold
*Recommended use with Grassroots Intake Manifold
CNC-Machined Billet Aluminum
1/2" Inside Diameter Ports
Grassroots Performance LS/VORTEC series throttle body use the 4-bolt mount pattern. A simple proven design that increases airflow with a bigger opening, also known as "BIG MOUTH". Improved horsepower and torque from 2500rpm through redline. OEM fitment for Throttle Position Sensor (TPS) and Idle Air Control Sensor (IACS).
*Fits OEM Manifolds with 4-bolt flange
4.8, 5.3, 6.0
LR4, LM4, LM7, L33, LQ4, LQ6
Cathedral Port head
Cable Throttle ONLY
LSX 102MM Aluminum Intake Manifold
LSX 102MM Cable Throttle Body
LSX Billet Fuel Rail Kit
Fuel Fittings Kit
Fel-Pro Genuine Intake Manifold Gasket Kit
This powerful Fuel Pressure Regulator has everything you need to complete your high-flow fuel system. A fuel pressure regulator can be found in a variety...View full product details