If your street rod or vintage muscle car has sat in a garage for any length of time, then you’ll likely be familiar with the odor of gasoline in the air. That’s because fuel permeates through regular rubber fuel lines at an alarming rate: in one year, a 2ft length of hose can lose as much as a gallon of gasoline to vapor. That’s not only a smelly nuisance, but an alarming waste of gas.

Modern fuels are even tougher on fuel lines than in the past. Gasoline is now a cocktail of regular gas and additives that increase the octane number, clean the engine, or improve the sustainability of the fuel. The most notable additive is ethanol. Present in pump gas at up to 10% (E10), ethanol gradually dries the rubber hose out as the vapor seeps through it, causing traditional fuel lines to harden and crack, and amplifying the risk of a dangerous fuel leak.

Plain rubber fuel hoses just aren't designed to stand up to today's fuels. The rubber allows fuel to permeate through, and over time can harden and crack, leading to dangerous fuel leaks.

“Today’s gasoline chews up fuel lines,” confirms Todd Crays, senior merchandising manager for Earl’s. “The days when traditional rubber hose was up to the task, are gone.”

Earl’s has a proven solution to the problem of permeable rubber products in the form of its Vapor Guard line of hoses, fittings and clamps. Crucially, Vapor Guard is an affordable replacement for traditional neoprene/rubber hose. Earl’s supplies Vapor Guard in 10ft or 20ft lengths as a standalone product, but even a kit containing 20ft of EFI-grade hose, four fittings, clamps and an inline fuel filter – enough to plumb a car and a returnless Sniper EFI system – costs less than $170, compared with more than double that figure for a premium, stainless-steel-braided alternative.

1. Black Brite Dip anodozing offers long-life even when used with today’s harsh fuels 2. AN, SAE port & NPT hose ends available 3. Brazed bent-tube assembly provides unsurpassed strength 4. Three styles of stainless steel clamps available 5. Hose ends are adjustable in orientation after assembly for final clocking during installation 6. Exterior Cover - Extreme tolerance of heat and ozone 7. Reinforcement Braid - Aramid material (EFI hose only) is used to provide the high pressure rating that fuel injection requires 8. Vapor Guard Barrier - Thermoplastic layer provides superior fuel isolation virtually eliminating vapors from escaping through the hose 9. Primary Barrier Liner - Initial layer offers high resistance to heat and aggressive fuels 10. Vapor-Guard Retention Bead - retains hose under pressure while assuring hose liner is not damaged

Earl’s Vapor Guard is available in two inner diameters – 5/16-inch and 3/8-inch – and is compatible with all popular fuels. The list includes leaded and unleaded gasoline, diesel, biodiesel, E85, methanol, ethanol and gasohol. Fully EPA-compliant and CARB-certificated, it’s popular with owners of street rods, classic and muscle cars, and even weekend bracket racers running non-boosted drivetrains.

Materials technology is key to the hose achieving excellent performance at an economical price. It is comprised of up to four distinct layers, each made of a different material to fulfill its purpose. The innermost layer or ‘Primary Barrier Liner’ offers high resistance to heat and aggressive fuels. The second layer is the thermoplastic Vapor Guard Barrier, which performs a similar function to the inner liner of a tire, isolating the fuel in the hose and stopping almost all vapors from escaping to the outside.

Surrounding that barrier is the Reinforcement Braid. Both sizes of Earl’s Vapor Guard hoses are in turn available in two different versions. The first is designed for use in a carburetor-based fuel system up to 50psi. The second, higher-pressure product handles aftermarket EFI systems up to 225psi. In the EFI version, the Reinforcement Braid’s woven Aramid fiber – similar to the material used in protective workwear and body armor –gives the hose the necessary strength, even without a stainless-steel outer layer.

Vapor Guard hose is available in two different sizes (3/8-inch and 5/16-inch) and two pressure ratings (50 PSI for carbureted applications, 225 PSI maximum for EFI applications)

Both types of Vapor Guard are finished off with an exterior cover that offers extreme tolerance to heat and ozone that might otherwise degrade the hose.

As you’d expect from a product designed to minimize permeation, care has been given to the installation process. Earl’s Vapor Guard hose has a complementary range of fittings and clamps that are designed to be easy to work with and minimize the risk of damage to the all-important thermoplastic barrier layer.

Fittings are available in AN, SAE port and NPT styles and are formed from a brazed bent-tube assembly for long-lasting strength. Like the hose itself, the fittings are resistant to corrosive modern fuels, in this case thanks to the surface being anodized and black Brite Dipped.

All fittings have a Vapor Guard Retention Bead that keeps the hose in place under pressure. Enthusiasts can replumb their cars without resorting to special tools: you simply slide the hose over the Retention Bead on the fitting, adjust the orientation as necessary, slip a clamp over the top, and tighten. The stainless-steel clamps are available in three styles – single- or dual-layer crimp-on, or screw-on.

“This is a perfect, economical product for the do-it-yourself car builder,” says Todd Crays. “There’s no cross threading the collets on an AN fitting or ruining a fitting by trial and error. With the Vapor Guard system, you simply slide it on, clamp it with a pair of pliers or a screwdriver, and check for leaks once you start it up.”

Crays adds that Earl’s Vapor Guard meets a variety of needs. Some owners use a short length to replace a worn-out section of existing hose; others opt to replumb their entire vehicle with this more durable product, perhaps in conjunction with an EFI conversion. Standardized sizing and fittings across the carburetor and EFI products even provide the flexibility to fit the EFI hose to a carbureted machine while future proofing it for an upgrade to fuel injection further down the road. But whatever the application, those anti-social garage odors are a thing of the past.