Plumbing your racecar can be tricky, especially when dealing with more corrosive race fuels and a high base fuel pressure. Race fuels can eat away at the rubber lining of hoses causing cracking, leaks, premature fuel filter clogging, can soften some of the more durable rubber lined hoses, and will allow the strong fuel odor to permeate through the line; now add high fuel pressure to that and failures will happen quickly and suddenly.

Earl’s Performance Plumbing has been providing plumbing solutions to the motorsports aftermarket for close to 50 years, starting out by selling surplus mil-spec plumbing directly to the racing industry before finally deciding to develop their own plumbing components when the surplus ran out. Having this many years of experience and being a pioneer in developing motorsports grade plumbing gives Earl’s the edge when it comes to creating new plumbing solutions to handle modern racing applications.

In the video above, Jeremy Stoermer dissects Earl’s UltraPro series fittings and hose to explain their unique design, specially made to handle the extreme environments seen in most forms of racing.

Hose Construction

It starts with the waxy polytetrafluoroethylene (PTFE) inner liner, also known as Teflon (DuPont’s trademark name), which dissipates static charges and has hydrophobic properties that prevent fluid attraction and wetting of the liner to block vapor permeation of all automotive fluids and lubricants. PTFE is also known to have one of the lowest coefficients of friction of any solid material, which improves overall fuel flow over a standard rubber lined hose.

The strength of the hose is further improved with the addition of a fiberglass wrap to reinforce the PTFE inner liner, which is then protected with a stainless steel or polyester outer braid. The double-helix design of the inner liner also prevents kinks and improves flexibility for maximum flow even with tight bends. Depending on the braided material chosen, the UltraPro hose also weigh as much as 67-percent less than its rubber lined sibling, providing great weight savings for racing platforms.

Earl's UltraPro hose is offered in both stainless steel (left) and polyester braid.

The FittingsThe UltraPro fittings are offered with either twist-on or crimp-on fittings to meet the requirements of any component. Earl’s goes a step further in the design of their UltraPro fittings by utilizing 2024-T8 aluminum alloy for ultimate strength and reliability in high stress racing conditions, which are then coated in Earl’s “Ano-Tuff” hard anodizing to prevent scuffs and scratches. The swivel fittings also feature “dynamic swivel” and durable fluoroelastomer seals for a full 360 degrees of rotation without having to worry about causing leaks.

The double-helix ribbed design of the hose not only provides extreme flexibility, but also serves as a form of positive engagement for the fittings. The included “olive” threads onto the ribbed inner liner to retain the hose within the fitting under high pressure or tugging.

The “olive” (center) is used to compress the inner liner within the fitting to prevent the hose from coming unseated.

The fittings are available with replacement twist on nuts that are also offered in several different colors for personal styling and is available in every popular hose size, from -6 all the way up to -20.