LS Swap AN Fuel Line Kit — Return-Less (PTFE AN-6)

LS Swap AN Fuel Line Kit — Return-Less (PTFE AN-6)

One clean AN-6 feed to the rail—pressure control and the return happen at the tank. This kit bundles PTFE hose, matched AN fittings, the Corvette-style 58 PSI filter/regulator, and mounting hardware so your LS swap fuels like a modern car: quiet, stable, and leak-free—even on E85.

What’s in the kit

• PTFE AN-6 hose — choose length (20 / 30 / 40 ft) and color.
• PTFE hose-end fittings (8 total) — 4× straight, 2× 45°, 2× 90°.
• 1× 3/8″ EFI quick-connect → AN-6 fitting (common LS rail feed).
• Corvette-style 58 PSI filter/regulator — rear-mount for return-less layout.
• 10-pack rubber-cushioned line clamps — tidy, rattle-free routing.

How it plumbs (return-less)

1. Pump → IN on Corvette filter/reg (mounted near tank).
2. Filter/reg OUT → single AN-6 feed to the rail (use the included 3/8″ EFI quick-connect adapter).
3. Filter/reg RETURN → back to tank/sending-unit return port.

Most LS rails target ~58 PSI. Regulating at the rear shortens the return path, reduces heat in the bay, and smooths idle/starts.

Which length should I choose?

• 20 ft — cars/short wheelbase, tight routing.
• 30 ft — most trucks/SUVs (typical squarebody routing).
• 40 ft — long wheelbase, service loops, or complex paths.

Other items needed for a successful install

• Adapter fittings from tank sending unit (return & vent as required) — browse AN adapter fittings.
• Adapter fittings for inline pump (if used) — see AN adapter fittings.

Recommended add-ons

• Transmission adapter fittings → AN male (if plumbing cooler lines now).
• Extra PTFE hose-end fittings (if you need more angles or service loops).
• Fuel pressure regulators (front-mount options for high-flow/boost builds).
• ≤10 µm EFI fuel filters (if not using the Corvette filter/reg as your pressure filter).
• Install tools — cutter, vise jaws, AN wrenches for clean PTFE assembly.

Why this kit works

• PTFE throughout for E85/ethanol compatibility and minimal vapor smell.
• Matched fittings reduce leak points and headaches—no hunting for angles mid-install.
• Rear regulation keeps pressure steady at the source and cleans up the engine bay.
• Clamps included so your routing is neat and rattle-free from day one.

Important notes

• The Corvette-style filter/regulator is great for street/strip. Extremely high-flow pumps (≥ 255–340 LPH) or boosted combos may need a front-mounted, high-flow return-style regulator from our regulator collection.
• Confirm your rail connection: most OE LS feeds are 3/8″ EFI quick-connect (included). Aftermarket/early rails may differ—grab the right piece from AN adapter fittings.

Install instructions & Hose 101

• Installation hub — diagrams, routing tips, best practices.
• PTFE hose & AN fittings — step-by-step (cutting, clocking, leak-check).
• AN Hose 101 tech articles — regulators, filters, routing, and more.

FAQs