The XS Intake Manifold breaks the mold of the existing intake manifold 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 we moved it….inside the intake manifold!  After testing all the mainstream manifolds available, our manifold has done what no other did…make horsepower and torque gains on a stock engine with gains increasing as the engine got more aggressive with cam and exhaust upgrades.  All other manifolds lost on HP or Torque to make the gain on the other.
This move presents several engineering challenges we overcame.  First, fuel must be delivered to the fuel rails.  To do this, we 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.  We do 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.  We ended with staggered runners with 3 lengths to optimize overall performance. Burst testing was conducted to ensure structural integrity beyond 6 bar (86psi).  We 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 & 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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