EVIL ENERGY 6AN PTFE Fuel Line Kit, E85 Compatible PTFE Fuel Hose Kit 16/20FT, 6AN/8AN/10AN Nylon Braided Line Hose with Adjustion Wrench

Q: Do I need a special crimping machine to install the fittings, or can I assemble the line myself?

A: No crimping machine is required. These are reusable, screw-together AN hose ends — the fitting threads onto the hose over an internal olive/ferrule, then a wrench and vice jaws are used to tighten it by hand, unlike permanently crimped hose assemblies that need a hydraulic press.

Q: Do the AN fittings need Teflon tape or thread sealant to seal properly?

A: No. AN fittings use a 37-degree flare seal combined with an O-ring for a leak-resistant connection at metal-to-metal contact, so no thread tape or sealant is needed on the flare joint — sealant is only ever used on separate NPT-threaded ports if your system has them.

Q: Can these AN fittings connect directly to my car's factory (OEM) fuel line quick-connects?

A: Not directly. PTFE AN hose ends use a 37-degree female flare fitting, which is a different sealing standard from OEM barbed or push-lock quick-connect fittings, so you'll typically need a dedicated AN-to-OEM quick-connect adapter to bridge the two systems.

Q: What should I inspect before installing the fittings to avoid contaminating my fuel system?

A: It's worth checking the fitting threads and bore for leftover internal burrs or metal shavings from the manufacturing process, then clearing them out with a blast of compressed air and a visual check before installation, since debris left inside can damage fuel injectors downstream.

Q: Can I disassemble and reuse the same fitting if I need to rebuild or modify the line later?

A: Yes, the fittings are designed to be reusable rather than permanently crimped, so the line can be taken apart and rebuilt for routing changes; when reassembling, it's good practice to inspect or replace the internal olive/ferrule so the seal stays leak-free each time.

Q: How do I check a self-assembled PTFE line for leaks before installing it in the car?

A: A common method is to cap one end of the finished hose, pressurize it, and submerge the assembly (or apply soapy water) to look for bubbles — small bubbles occasionally appearing right at the swivel pin are normal and not necessarily a sign of a leak, but any bubbling directly at the flare or nut indicates the joint needs to be re-tightened or reassembled.

Q: What kind of applications is this fuel line typically used for besides EFI fuel supply?

A: Beyond primary fuel supply lines, PTFE-lined AN hose in this construction is also commonly run for fuel return/vapor return lines, boost/vacuum reference lines, and even transmission cooler or engine oil lines, since the PTFE liner and pressure rating hold up across multiple fluid types in the same build.

Q: Is it better to have a shop crimp the hose ends instead of using the reusable screw-on fittings?

A: Both approaches are used in the industry — reusable screw-together fittings let you rebuild or re-route a line yourself with basic tools, while professionally crimped ends create a more permanent, factory-style joint that some builders prefer for lines that won't be serviced again, such as transmission cooler lines; it comes down to whether you value rebuildability or a permanent, shop-finished joint more.

Q: How is PTFE hose different from the OE-style nylon fuel line already on my car, and can they use the same fittings?

A: PTFE (Teflon) is a distinct material from factory single-layer nylon fuel line, and the two are not interchangeable — PTFE hose requires its own AN-flare-style fittings (typically -6AN 37-degree female flare), so if you're converting a section of your fuel system to PTFE, the connecting ends on that section need to be PTFE-specific, not the barbed clips used on OE nylon line.