EVIL ENERGY Performance Parts Guide: Fuel Systems, Intakes, and Plumbing

Selecting the Right Fuel Delivery Setup for EFI and LS Swaps

When transitioning a classic chassis to modern electronic fuel injection (EFI) or executing an LS swap, fuel delivery is often the most critical system to engineer properly. Unlike legacy mechanical pumps that operate between 4 and 7 PSI, modern EFI systems demand steady, high-pressure fuel—frequently fixed around 58 PSI for standard GM LS rails, or dynamically modulated via a 20–120 PSI boost-referenced bypass regulator. Inadequate volume or fluctuating pressure can cause sudden lean spikes under acceleration, endangering internal engine components.

EVIL ENERGY addresses these swap challenges with unified conversion packages that combine external frame-mounted pumps or high-flow 300+ LPH electric pumps with compatible bypass regulators, filters, and AN plumbing. Using a return-style regulator near the fuel rail or fuel cell ensures continuous fuel circulation, which dramatically reduces fuel rail temperatures and prevents vapor lock during hot idle conditions.

• Check Pressure Specs: Match your intake setup with either a factory-calibrated 58 PSI regulator/filter unit for stock LS injectors or an adjustable 20–120 PSI bypass unit for custom aftermarket fuel rails.
• Filter Micron Rating: Run a coarse 100-micron pre-filter before external inline pumps to protect internal impellers, followed by a fine 10-micron post-filter to safeguard sensitive injector nozzles.
• Return Line Sizing: Ensure the return line is at least equal in internal diameter (minimum 6AN / 3/8-inch) to the supply line to prevent backpressure spikes at low engine loads.

PTFE vs. CPE Lines: Choosing the Best Plumbing for E85 and High Pressure

Plumbing a performance vehicle requires choosing between two predominant hose liner materials: Chlorinated Polyethylene (CPE) synthetic rubber and Polytetrafluoroethylene (PTFE). While stainless-steel or nylon-braided CPE hose is flexible and suitable for standard pump gasoline and oil cooler lines, modern fuels containing ethanol blends (E10, E85) can gradually degrade rubber compounds. Over extended periods, microscopic fuel vapors can permeate CPE walls, leading to persistent gasoline smells inside car interiors or garages.

EVIL ENERGY’s PTFE hose lines feature an extruded, chemically inert Teflon-style core reinforced with robust braided jackets. PTFE is impervious to aggressive ethanol blends, race fuels, methanol, motor oils, and brake fluids. Furthermore, its smooth interior wall provides lower friction flow and holds up under the rigorous pressure cycles common in high-horsepower forced-induction systems.

• Vapor Barrier Integrity: PTFE lines guarantee zero fuel smell permeation, making them the preferred choice for lines routed through interior tunnels or enclosed trunks.
• Working Pressure Headroom: Reinforced PTFE hose handles significantly higher burst pressures than standard rubber hose, offering added security in high-pressure fuel injection circuits.
• Assembly Technique: Unlike push-on or compression fittings for rubber hose, PTFE fittings use a dedicated brass olive (ferrule) between the liner and the fitting body. Take care to seat the olive smoothly over the PTFE liner during installation.

Air Intake, Throttle Bodies, and Manifold Upgrades for Performance Builds

Fuel management represents only half of the combustion equation; efficient airflow into the combustion chambers is equally vital. On modern electronically controlled V8 platforms—such as GM 6.2L LS3/L99 engines and Dodge 5.7L HEMI trucks—the factory throttle body and air intake box can create restrictive pressure drops as engine speeds climb. Enlarging the intake bore allows the engine to breathe deeper, improving throttle tip-in and mid-range torque.

EVIL ENERGY provides engineered matched bundles, such as cold air intake piping paired with enlarged electronic throttle bodies (85mm for modern HEMIs and 92mm to 102mm for GM LS platforms). These units retain factory drive-by-wire Throttle Position Sensor (TPS) communication while presenting a wider cross-sectional area to incoming air. When coupled with smooth aluminum intake tubing and oiled cone filters, they help minimize intake air temperatures and stabilize runner velocity.

• Flange and Bolt Pattern: Confirm whether your intake manifold utilizes a 4-bolt or 3-bolt throttle body pattern, and check that the manifold snout diameter accommodates the larger throttle blade without binding.
• Drive-by-Wire Calibration: Replacing an electronic throttle body increases initial airflow at low blade angles. Plan for an ECU throttle relearn or custom engine tune to optimize idle stability and acceleration fueling.
• Thermal Shielding: Utilize included air box heat shields to isolate the conical air filter from hot under-hood radiator wash, drawing denser air from inner fender wells.