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XS Intake Manifold for Gen 4 LS3 Engines

Posted By: Evan J. Smith
XS Intake Manifold for Gen 4 LS3 Engines
By Evan J. Smith
LS 3 owners have a new option for induction with the XS Intake Manifold, which breaks the mold of the existing intake architecture to maximize available space under the hood. When designing the optimum intake runner length and shape the fuel rail gets in the way, so they moved it inside the intake manifold.
According to XS, the intake even made gains in horsepower and torque gains on a stock engine with gains increasing as the engine got more aggressive with cam and exhaust upgrades.
This move presents several engineering challenges that they overcame. First, fuel must be delivered to the fuel rails. To do this, they engineered and manufactured a bespoke fuel rail for this product with a feed port in a precise location to interface with a custom fitting. This fitting passes through the intake manifold housing through a provision engineered into the upper shell gasket. A fuel crossover feeds the opposite bank. Next, injector electrical connectors need to find their way inside the intake manifold. They did this by using a short injector jumper harness which passes through a sealed grommet for each injector jumper. All custom molded seals are engineering to seal this innovative packaging strategy.
The intake manifold runners were developed using CFD (Computational Fluid Dynamics) then several runner designs were tested on the engine dyno to validate the performance gains. XS ended with staggered runners with three lengths to optimize overall performance. Burst testing was conducted to ensure structural integrity beyond 6 bar (86psi). XS will be releasing the first production pieces to several key partners to conduct further testing in various combinations.
The XS intake manifold fits all LS3-style cylinder head ports including L92, L99, L76, L77, LY6, LY2, L20, LMF, LC9, LH8, LH9, L9H and L94. Even with the additional features and components required for this unique design, Performance Design is able to offer this intake manifold at a price significantly less than existing products on the market.
Specifications and Features
• Injection molded glass reinforced nylon construction
• Modular runners with 3 staggered lengths for best performance 
• Billet fuel rails with external quick disconnect near stock location
• Accepts standard EV6 LS3/LS7-style injectors
• Injector extension wires passed through sealed grommets
• 90-103mm or 112mm forward facing throttle body flange
• Carbon fiber center bolt cover
• Factory MAP sensor location
• PCV and Canister Purge Solenoid OEM connections
• Includes stainless steel hardware for installation
• Includes molded port, plenum and throttle seals
• Intake can be reversed on the engine

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