Bill, Your absolutely right, without the lining the fuel and additives will eat away at the rubber little by little. That's why I sell a higher grade line than is necessary. Fuel line is cheap, but the good stuff is more expensive. John Hervey www.specialTauto.com << Pressure problem with traditional rubber fuel line isn't that it will blow itself apart (although it probably wouldn't stay on hose barb without a clamp), problem is high pressure will act like a pressure washer and break off miniscule bits of rubber that, however tiny, will nevertheless foul fuel injectors. Sounds reasonable? This is my first fuel injected car, so don't get me to lying... >>